... voltage:36V-60V specification:16"-18" efficiency:>=82% power:350W-500W 1.brushless,used for long time( ... need to maintain2.less space and weight,great power,simple construction3.excellent starting performance,no magnet-hysteresis ... capacity4.no spark,no electric interference,explosion prevention5.high efficiency,less electric power consumption6.large starting power,strong output fuction, stepless ...