Shop name:Chong Qing Shuo Yue Ke Ji You Xian Gong Si [Converter Function]: The battery adapter can make listed 20V max lithium batteries use on for 18V Ni- cordless power tools , and let you Enjoy the benefits of extended run-time of Li-Ion Batteries on your existing 18V tools. [Applicable Battery Models]: The bottom of this adapter can allows for use of 20V lithium batteries, Compatible with WA3520 WA3525 WA3575 WA3578 WA3511 WA3512 WG153 WA3512.1 WA3522 WA3523 WA3544 WA3671 WG151s WG251s WG255s WG540s WG545s WG890 WG891 20V Batteries etc. (Default without battery) [Replace 18V NiMH Battery]: Replacement for 18V Ni- Battery. Compatible with 18 Volt cordless power tools models WA3127 WA3152 WG150 WG150s WG152 WG250 WG541 WG900 WG901 WG901.1, But can not fit for 20V tools. [Using Notes] 1.CANNOT charge battery with this Adapter! Please remove the adapter before charging battery (Use the battery charger) ; 2. Maximum initial battery voltage(measured without a workload) is 20volts,Nominal voltage is 18volts. 3. Please remove it from the battery when not in use, Safe to use. The bottom of this adapter is only compatible with 18V/ 20V MAX lithium-Ion battery: eg. WA3520 WA3525 WA3575 WA3578 WA3511 WA3512 WA3512.1 WA3522 WA3523 WA3544 WA3671 WG151s WG251s WG255s WG540s WG545s WG890 WG891 20V Batteries etc.. The top of this adapter is only compatible with 18V Ni- cordless power tools. eg. WA3127 WA3152 WG150 WG150s WG152 WG153 WG250 WG541 WG900 WG901 WG901.1, But can not fit for 20V tools. NOTE: 1. CANNOT charge battery with this Adapter! Please remove the adapter before charging battery; 2. Please remove it from the battery when not in use, Safe to use Due to different production batches, there may be slight differences in products. Colour:Black Material:Plastic Package Contents: 1 x Battery Adapter(Batteries not included) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.