Built-in rubber insert to hold plug steadily.
Use with 3/8" drive ratchet
14mm Socket: Boxer motors liquid cooled and on, Non-brick K bike motors, S bike motors.
16mm Socket: Boxer motors oil cooled, F twin motors.
18mm Socket: K brick motors.
Unsure which you need? Give us a call at 616-530-6900 and we'll help you out!