diff --git a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ClusterExtensionType_Get.json b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ClusterExtensionType_Get.json
new file mode 100644
index 000000000000..00d08509e4b8
--- /dev/null
+++ b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ClusterExtensionType_Get.json
@@ -0,0 +1,43 @@
+{
+  "parameters": {
+    "subscriptionId": "aaaaaaaaaa",
+    "resourceGroupName": "rgextensionTypes",
+    "clusterRp": "Microsoft.ContainerService",
+    "clusterType": "managedClusters",
+    "clusterName": "aaaaaaaaaaaaaaaaaaaaa",
+    "api-version": "2021-05-01-preview",
+    "extensionTypeName": "aaaaaa"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "properties": {
+          "releaseTrains": [
+            "aaaaaaaaaaaaaaaaaaaaaa"
+          ],
+          "clusterTypes": "connectedClusters",
+          "supportedScopes": {
+            "defaultScope": "aaaaaaaaaaa",
+            "clusterScopeSettings": {
+              "properties": {
+                "allowMultipleInstances": true,
+                "defaultReleaseNamespace": "aaaaaaaaaaaaaaaaaaaaaaa"
+              },
+              "id": "aaaaaaaaaaaaaaaa",
+              "name": "aaaaaaaaaa",
+              "type": "aaaaaaaaaaaaaaaaaaa"
+            }
+          }
+        },
+        "systemData": {
+          "createdBy": "aaaaaaaa",
+          "createdByType": "User",
+          "createdAt": "2021-04-14T22:44:27.144Z",
+          "lastModifiedBy": "aaaaaaaaa",
+          "lastModifiedByType": "User",
+          "lastModifiedAt": "2021-04-14T22:44:27.144Z"
+        }
+      }
+    }
+  }
+}
diff --git a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ClusterExtensionTypes_List.json b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ClusterExtensionTypes_List.json
new file mode 100644
index 000000000000..36c86047383c
--- /dev/null
+++ b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ClusterExtensionTypes_List.json
@@ -0,0 +1,46 @@
+{
+  "parameters": {
+    "subscriptionId": "aaaaaaaaaa",
+    "resourceGroupName": "rgextensionTypes",
+    "clusterRp": "Microsoft.ContainerService",
+    "clusterName": "aaaaaaaaaaaaaaaaaaaaa",
+    "api-version": "2021-05-01-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "value": [
+          {
+            "properties": {
+              "releaseTrains": [
+                "aaaaaaaaaaaaaaaaaaaaaa"
+              ],
+              "clusterTypes": "connectedClusters",
+              "supportedScopes": {
+                "defaultScope": "aaaaaaaaaaa",
+                "clusterScopeSettings": {
+                  "properties": {
+                    "allowMultipleInstances": true,
+                    "defaultReleaseNamespace": "aaaaaaaaaaaaaaaaaaaaaaa"
+                  },
+                  "id": "aaaaaaaaaaaaaaaa",
+                  "name": "aaaaaaaaaa",
+                  "type": "aaaaaaaaaaaaaaaaaaa"
+                }
+              }
+            },
+            "systemData": {
+              "createdBy": "aaaaaaaa",
+              "createdByType": "User",
+              "createdAt": "2021-04-14T22:44:27.144Z",
+              "lastModifiedBy": "aaaaaaaaa",
+              "lastModifiedByType": "User",
+              "lastModifiedAt": "2021-04-14T22:44:27.144Z"
+            }
+          }
+        ],
+        "nextLink": "aaaaaaaaaaaaaaaaaaaaa"
+      }
+    }
+  }
+}
diff --git a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ExtensionTypeVersions_List.json b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ExtensionTypeVersions_List.json
new file mode 100644
index 000000000000..de2110441dc5
--- /dev/null
+++ b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/ExtensionTypeVersions_List.json
@@ -0,0 +1,31 @@
+{
+  "parameters": {
+    "subscriptionId": "aaaaaaaaaa",
+    "location": "aaaaaa",
+    "extensionTypeName": "aaaaaa",
+    "api-version": "2021-05-01-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "versions": [
+          {
+            "releaseTrain": "aaaa",
+            "versions": [
+              "aaaaaaaaaaaaaa"
+            ]
+          }
+        ],
+        "nextLink": "aaa",
+        "systemData": {
+          "createdBy": "aaaaaaaa",
+          "createdByType": "User",
+          "createdAt": "2021-04-14T22:44:27.144Z",
+          "lastModifiedBy": "aaaaaaaaa",
+          "lastModifiedByType": "User",
+          "lastModifiedAt": "2021-04-14T22:44:27.144Z"
+        }
+      }
+    }
+  }
+}
diff --git a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/LocationExtensionTypes_List.json b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/LocationExtensionTypes_List.json
new file mode 100644
index 000000000000..27eee20dca0a
--- /dev/null
+++ b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/LocationExtensionTypes_List.json
@@ -0,0 +1,44 @@
+{
+  "parameters": {
+    "subscriptionId": "aaaaaaaaaa",
+    "location": "aaaaaa",
+    "api-version": "2021-05-01-preview"
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "value": [
+          {
+            "properties": {
+              "releaseTrains": [
+                "aaaaaaaaaaaaaaaaaaaaaa"
+              ],
+              "clusterTypes": "connectedClusters",
+              "supportedScopes": {
+                "defaultScope": "aaaaaaaaaaa",
+                "clusterScopeSettings": {
+                  "properties": {
+                    "allowMultipleInstances": true,
+                    "defaultReleaseNamespace": "aaaaaaaaaaaaaaaaaaaaaaa"
+                  },
+                  "id": "aaaaaaaaaaaaaaaa",
+                  "name": "aaaaaaaaaa",
+                  "type": "aaaaaaaaaaaaaaaaaaa"
+                }
+              }
+            },
+            "systemData": {
+              "createdBy": "aaaaaaaa",
+              "createdByType": "User",
+              "createdAt": "2021-04-14T22:44:27.144Z",
+              "lastModifiedBy": "aaaaaaaaa",
+              "lastModifiedByType": "User",
+              "lastModifiedAt": "2021-04-14T22:44:27.144Z"
+            }
+          }
+        ],
+        "nextLink": "aaaaaaaaaaaaaaaaaaaaa"
+      }
+    }
+  }
+}
diff --git a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/OperationsList.json b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/OperationsList.json
index b63a0d376b56..ef15e52b5903 100644
--- a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/OperationsList.json
+++ b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/examples/OperationsList.json
@@ -92,6 +92,17 @@
           },
           "isDataAction": false,
           "origin": "user,system"
+        },
+        {
+          "name": "Microsoft.KubernetesConfiguration/extensionTypes/read",
+          "display": {
+            "provider": "Microsoft.KubernetesConfiguration",
+            "resource": "extensionTypes",
+            "operation": "Get Kubernetes Configuration Available Extensions",
+            " provider": "Microsoft Kuberntes Configuration"
+          },
+          "isDataAction": false,
+          "origin": "user,system"
         }
       ]
     }
diff --git a/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/extensionTypes.json b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/extensionTypes.json
new file mode 100644
index 000000000000..ef25065a4138
--- /dev/null
+++ b/specification/kubernetesconfiguration/resource-manager/Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/extensionTypes.json
@@ -0,0 +1,412 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "version": "2021-05-01-preview",
+    "title": "ExtensionTypes",
+    "description": "Use these APIs to create extension resources through ARM, for Kubernetes Clusters."
+  },
+  "host": "management.azure.com",
+  "schemes": [
+    "https"
+  ],
+  "consumes": [
+    "application/json"
+  ],
+  "produces": [
+    "application/json"
+  ],
+  "security": [
+    {
+      "azure_auth": [
+        "user_impersonation"
+      ]
+    }
+  ],
+  "securityDefinitions": {
+    "azure_auth": {
+      "type": "oauth2",
+      "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
+      "flow": "implicit",
+      "description": "Azure Active Directory OAuth2 Flow",
+      "scopes": {
+        "user_impersonation": "impersonate your user account"
+      }
+    }
+  },
+  "paths": {
+    "/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/{clusterRp}/{clusterType}/{clusterName}/providers/Microsoft.KubernetesConfiguration/extensionTypes/{extensionTypeName}": {
+      "get": {
+        "description": "Get Extension Type details",
+        "operationId": "ClusterExtensionType_Get",
+        "x-ms-examples": {
+          "ClusterExtensionType_Get_MaximumSet_Gen": {
+            "$ref": "./examples/ClusterExtensionType_Get.json"
+          }
+        },
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ResourceGroupNameParameter"
+          },
+          {
+            "$ref": "#/parameters/ClusterRpParameter"
+          },
+          {
+            "$ref": "#/parameters/ClusterTypeParameter"
+          },
+          {
+            "$ref": "#/parameters/ClusterNameParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ApiVersionParameter"
+          },
+          {
+            "$ref": "#/parameters/ExtensionTypeNameParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK",
+            "schema": {
+              "$ref": "#/definitions/ExtensionType"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/ErrorResponse"
+            }
+          }
+        }
+      }
+    },
+    "/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/{clusterRp}/connectedClusters/{clusterName}/providers/Microsoft.KubernetesConfiguration/extensionTypes": {
+      "get": {
+        "description": "Get Extension Types",
+        "operationId": "ClusterExtensionTypes_List",
+        "x-ms-examples": {
+          "ClusterExtensionTypes_List_MaximumSet_Gen": {
+            "$ref": "./examples/ClusterExtensionTypes_List.json"
+          }
+        },
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ResourceGroupNameParameter"
+          },
+          {
+            "$ref": "#/parameters/ClusterRpParameter"
+          },
+          {
+            "$ref": "#/parameters/ClusterNameParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK",
+            "schema": {
+              "$ref": "#/definitions/ExtensionTypeList"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed.",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    },
+    "/subscriptions/{subscriptionId}/providers/Microsoft.KubernetesConfiguration/locations/{location}/extensionTypes/{extensionTypeName}/versions": {
+      "get": {
+        "description": "List available versions for an Extension Type",
+        "operationId": "ExtensionTypeVersions_List",
+        "x-ms-examples": {
+          "ExtensionTypeVersions_List_MaximumSet_Gen": {
+            "$ref": "./examples/ExtensionTypeVersions_List.json"
+          }
+        },
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "#/parameters/ExtensionLocationParameter"
+          },
+          {
+            "$ref": "#/parameters/ExtensionTypeNameParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK",
+            "schema": {
+              "$ref": "#/definitions/ExtensionVersionList"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink",
+          "itemName": "versions"
+        }
+      }
+    },
+    "/subscriptions/{subscriptionId}/providers/Microsoft.KubernetesConfiguration/locations/{location}/extensionTypes": {
+      "get": {
+        "tags": [
+          "ExtensionType"
+        ],
+        "description": "List all Extension Types",
+        "operationId": "LocationExtensionTypes_List",
+        "x-ms-examples": {
+          "LocationExtensionTypes_List_MaximumSet_Gen": {
+            "$ref": "./examples/LocationExtensionTypes_List.json"
+          }
+        },
+        "parameters": [
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "#/parameters/ExtensionLocationParameter"
+          },
+          {
+            "$ref": "../../../../../common-types/resource-management/v2/types.json#/parameters/ApiVersionParameter"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK",
+            "schema": {
+              "$ref": "#/definitions/ExtensionTypeList"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed",
+            "schema": {
+              "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-pageable": {
+          "nextLinkName": "nextLink"
+        }
+      }
+    }
+  },
+  "definitions": {
+    "ExtensionTypeList": {
+      "description": "List Extension Types",
+      "type": "object",
+      "properties": {
+        "value": {
+          "description": "The list of Extension Types",
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/ExtensionType"
+          }
+        },
+        "nextLink": {
+          "description": "The link to fetch the next page of Extension Types",
+          "type": "string"
+        }
+      }
+    },
+    "ExtensionType": {
+      "type": "object",
+      "description": "Represents an Extension Type.",
+      "required": [
+        "properties"
+      ],
+      "properties": {
+        "properties": {
+          "x-ms-client-flatten": true,
+          "$ref": "#/definitions/ExtensionTypeProperties",
+          "description": "Describes the Resource Type properties."
+        },
+        "systemData": {
+          "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/systemData",
+          "readOnly": true,
+          "description": "Metadata pertaining to creation and last modification of the resource."
+        }
+      }
+    },
+    "ExtensionTypeProperties": {
+      "description": "Properties of the connected cluster.",
+      "type": "object",
+      "properties": {
+        "releaseTrains": {
+          "readOnly": true,
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "description": "Extension release train: preview or stable"
+        },
+        "clusterTypes": {
+          "description": "Cluster types",
+          "readOnly": true,
+          "type": "string",
+          "enum": [
+            "connectedClusters",
+            "managedClusters"
+          ],
+          "x-ms-enum": {
+            "name": "clusterTypes",
+            "modelAsString": false
+          }
+        },
+        "supportedScopes": {
+          "readOnly": true,
+          "type": "object",
+          "description": "Extension scopes",
+          "$ref": "#/definitions/SupportedScopes"
+        }
+      }
+    },
+    "ExtensionVersionList": {
+      "description": "List versions for an Extension",
+      "type": "object",
+      "properties": {
+        "versions": {
+          "description": "Versions available for this Extension Type",
+          "type": "array",
+          "items": {
+            "type": "object",
+            "properties": {
+              "releaseTrain": {
+                "description": "The release train for this Extension Type",
+                "type": "string"
+              },
+              "versions": {
+                "type": "array",
+                "description": "Versions available for this Extension Type and release train",
+                "items": {
+                  "type": "string"
+                }
+              }
+            }
+          }
+        },
+        "nextLink": {
+          "description": "The link to fetch the next page of Extension Types",
+          "type": "string"
+        },
+        "systemData": {
+          "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/systemData",
+          "readOnly": true,
+          "description": "Metadata pertaining to creation and last modification of the resource."
+        }
+      }
+    },
+    "SupportedScopes": {
+      "type": "object",
+      "description": "Extension scopes",
+      "properties": {
+        "defaultScope": {
+          "type": "string",
+          "description": "Default extension scopes: cluster or namespace"
+        },
+        "clusterScopeSettings": {
+          "description": "Scope settings",
+          "$ref": "#/definitions/ClusterScopeSettings"
+        }
+      }
+    },
+    "ClusterScopeSettings": {
+      "type": "object",
+      "description": "Extension scope settings",
+      "properties": {
+        "properties": {
+          "type": "object",
+          "x-ms-client-flatten": true,
+          "description": "Extension scope settings",
+          "properties": {
+            "allowMultipleInstances": {
+              "type": "boolean",
+              "description": "Describes if multiple instances of the extension are allowed"
+            },
+            "defaultReleaseNamespace": {
+              "type": "string",
+              "description": "Default extension release namespace"
+            }
+          }
+        }
+      },
+      "allOf": [
+        {
+          "$ref": "../../../../../common-types/resource-management/v2/types.json#/definitions/ProxyResource"
+        }
+      ]
+    }
+  },
+  "parameters": {
+    "ClusterRpParameter": {
+      "name": "clusterRp",
+      "in": "path",
+      "required": true,
+      "type": "string",
+      "enum": [
+        "Microsoft.ContainerService",
+        "Microsoft.Kubernetes"
+      ],
+      "description": "The Kubernetes cluster RP - either Microsoft.ContainerService (for AKS clusters) or Microsoft.Kubernetes (for OnPrem K8S clusters).",
+      "x-ms-parameter-location": "method"
+    },
+    "ClusterTypeParameter": {
+      "name": "clusterType",
+      "in": "path",
+      "required": true,
+      "type": "string",
+      "enum": [
+        "managedClusters",
+        "connectedClusters"
+      ],
+      "description": "The Kubernetes cluster resource name - either managedClusters (for AKS clusters) or connectedClusters (for OnPrem K8S clusters).",
+      "x-ms-parameter-location": "method"
+    },
+    "ClusterNameParameter": {
+      "name": "clusterName",
+      "in": "path",
+      "required": true,
+      "type": "string",
+      "description": "The name of the kubernetes cluster.",
+      "x-ms-parameter-location": "method"
+    },
+    "ExtensionLocationParameter": {
+      "name": "location",
+      "in": "path",
+      "description": "extension location",
+      "required": true,
+      "type": "string",
+      "x-ms-parameter-location": "method"
+    },
+    "ExtensionTypeNameParameter": {
+      "name": "extensionTypeName",
+      "in": "path",
+      "required": true,
+      "type": "string",
+      "description": "Extension type name",
+      "x-ms-parameter-location": "method"
+    }
+  }
+}
diff --git a/specification/kubernetesconfiguration/resource-manager/readme.go.md b/specification/kubernetesconfiguration/resource-manager/readme.go.md
index 94001cc33664..04446f7a0fca 100644
--- a/specification/kubernetesconfiguration/resource-manager/readme.go.md
+++ b/specification/kubernetesconfiguration/resource-manager/readme.go.md
@@ -56,4 +56,4 @@ These settings apply only when `--tag=package-2020-07-01-preview --go` is specif
 Please also specify `--go-sdks-folder=<path to the root directory of your azure-sdk-for-go clone>`.
 ```yaml $(tag) == 'package-2020-07-01-preview' && $(go)
 namespace: kubernetesconfiguration
-output-folder: $(go-sdk-folder)/services/preview/$(namespace)/mgmt/2020-07-01-preview/$(namespace)
\ No newline at end of file
+output-folder: $(go-sdk-folder)/services/preview/$(namespace)/mgmt/2020-07-01-preview/$(namespace)
diff --git a/specification/kubernetesconfiguration/resource-manager/readme.md b/specification/kubernetesconfiguration/resource-manager/readme.md
index a37c0c3eee19..7c4056b6dab7 100644
--- a/specification/kubernetesconfiguration/resource-manager/readme.md
+++ b/specification/kubernetesconfiguration/resource-manager/readme.md
@@ -39,6 +39,7 @@ These settings apply only when `--tag=package-preview-2021-05` is specified on t
 ```yaml $(tag) == 'package-preview-2021-05'
 input-file:
   - Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/extensions.json
+  - Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/extensionTypes.json
   - Microsoft.KubernetesConfiguration/preview/2021-05-01-preview/kubernetesconfiguration.json
 ```
 ### Tag: package-2021-03