GOOFIT 39mm Piston Rings Kit for GY6 49cc 50cc 139qmb Taotao Baja Jonway Lance Scooter The item fits for GY6 49cc 50cc with 139qmb Engine. The piston diameter:39mm,piston pin diameter:12mm,length of piston pin:30mm Package including 39mm piston piston,piston pin,2 compression rings,2 wiper rings,oil ing,ring clips Arrival within 1-2 days (Sold by GOOFIT and Fulfilled by Amazon) Arrival within 7-15 days (Ships from and sold by GOOFIT)