Key Features: ➤ 【Compatibility Reminder】: Please be aware that this adapter is not compatible with Craftsman Older 20V Bolt-On, Professional-type Batteries, Also not compatible with Porter Cable, Black and Decker batteries. They possess different pin configurations and sizes, rendering them incompatible with this adapter.➤ 【Installation & Usage】: 1. When installing the adapter, a reassuring "click" sound signals the correct and stable connection after the relevant latch system locks. Initial installation may require a moderate push. If you find it unfamiliar to push directly, try pressing the V20 battery latch button first, then insert the adapter to the proper position. Release the battery latch button to swiftly complete the installation.➤ 2. Please check the battery levels of your related extended batteries when using the adapter to ensure optimal performance. Most tools feature built-in undervoltage protection BMS systems.➤ 【What's in the Box?】: You'll receive 1x Adapter Only (Battery & Tool Not Included).