Converter bottom: Compatible with BL series 18V lithium-ion batteries; Adapter Top: The top of the adapter is compatible with 20V cordless power tools (WG151, WG251, WG540, WG891, WG151, WG151.5, WG800.1 power tools can be used). The corresponding lithium battery is 20V WA3520 WA3525 WA3575 WA3578 power . The bottom of the converter is suitable for battery models:18V lithium battery For the conversion of 18V lithium battery to 6-pin 20V lithium battery tool, through this converter, you can use 18V lithium battery on 6-pin 20V lithium battery tool, so that your 18V lithium battery can be compatible with 6-pin 20V lithium battery tool sharing battery. This converter does not support () 18V lithium battery and 20V lithium battery shared charger! Precautions: 1. The adapter has a protective plate. When not in use for a long time, separate the battery from the adapter to avoid damage to the battery 2. There is only one adapter, not including batteries and electric drill tools. The