This is the Robinson Racing 1/8" to 5mm Reducer Sleeve. This sleeve will allow you to use 5mm bore pinion gears on motors that have an 1/8" shaft.
Monday, Mar 15 2021 (5 weeks ago)
Robinson Racing 3.17mm to 5mm Reducer Sleeve (1/8" to 5mm)
Stripped out almost instantly 3 times now need a better option for 3mm shaft