Motor Brand:UNITE 1). This kit is for the bike that using the V brake on the rear wheel. If your bike uses disc brake or coaster brake, this kit does not compatible with that bike, please choose other kits. If you can not sure your bike type, please send me your bike picture, so I can recommend you the correct kit. 2). The motor bracket maybe does not fit your bike frame, this you need to modify the bracket by yourself, please confirm this. If you do not know how to modify, please send me your bike picture, so I can give you suggestion. 4). The difference between 24V and 36V is the working current, if you want to ride longer, I recommend 36V kit. 5)This controller comes with 1 fuse wire and 3 fuses, if you burn 1 fuse, you'd better note what makes it burnt and avoid this happen again, or please feel free to contact me for help. 6). This item has 2 throttle types for choice, if you want the twist type, please choose the "key throttle" option, and if you want the thumb type, please choose the "thumb throttle" option, thank you.