If you would like to add a little extra propulsion power to your bike and transform a standard bicycle into an e-bike, you might be interesting to this kit.However when you use this kit, please don't treat your bicycle as a 100% electric bicycle) . The whole set contains batteries, motors and installation packs. The motors are waterproof. The motors will heat up when they are running, but they are absolutely normal. The quality is very good! Battery: 48V 4.0 AH Pure battery life: 20-25 km Power status: 30-35 km Pure electric speed: 25-30km/h Battery maximum discharge current: 10AH Charging time: 2-3 hours Charging and discharging times: 500 times Battery: 48V 6.0 AH Pure battery life: 30-35 km Power status: 40-45 km Pure electric speed: 25-30km/h Battery maximum discharge current: 15AH Charging time: 3-4 hours Charging and discharging times: 500 times Battery: 48V 7.8 AH Pure battery life: 35-40 km Power status: 50-55 km Pure electric speed: 25-30km/h Battery maximum discharge current: 15AH Charging time: 3-4 hours Charging and discharging times: 500 times package: 1.1*Booster 2.1*Battery withBattery pack 3.1*Charger 4.1*switch 
