1# @ohos.app.ability.ExtensionAbility (ExtensionAbility Base Class) 2 3**ExtensionAbility** is the base class for scenario-specific ExtensionAbilities. It is inherited from [Ability](js-apis-app-ability-ability.md), with no property or method added. You cannot inherit from this base class. For details about the inheritance relationship of each ability, see [Inheritance Relationship](./js-apis-app-ability-ability.md#ability-inheritance-relationship). 4 5> **NOTE** 6> 7> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version. 8> 9> The APIs of this module can be used only in the stage model. 10 11## Modules to Import 12 13```ts 14import { ExtensionAbility } from '@kit.AbilityKit'; 15``` 16 17**Atomic service API**: This API can be used in atomic services since API version 11. 18 19**System capability**: SystemCapability.Ability.AbilityRuntime.AbilityCore 20