?? 3 speed switches – High speed, medium speed and low speed, fit for most 22.2mm diameter handle ?? Real-time Display – It is a digital data display, intuitive and convenient, you can accurately determine the static battery power and static distance ?? AccuratelyJudge Battery??s Condition – By turning the real-time voltage value can accurately determine the judge the of lithium battery and the remaining amount of electricity ?? Universal Voltage – This Bike Throttle Grip is fit for 12-84V electric bike or scooters, tricycle, and other electric vehicle. Also can identify voltage automatically, real-time display the data. (12V, 24V, 36V, 48V, 60V, 72V electric vehicles can be used directly, part of the 84V electric vehicles can also be used.) ?? Aluminium Alloy Material – Smooth surface, make the driver comfortable during driving and give more guarantee on safety Two 6V string into 12V or use 12V 24V dual drive car.