... 16inch .10inch and suitable for any size of wheel 4.hub motor5.high efficiency,less electric power consumption6.large starting power ... water-proof function9.brushless,used for long time(bearing),no need to maintain10.less space and weight,great power, ... creeping slop capacity12.no spark,no electric interference,explosion preventionSize 8''-3.75''/16-3.0inch 10-3.0inchBolt Circle 5x4.5''Hub Hole 2. ...