... °CHub MaterialAluminum, Steel, Sintered Bronze, Brass, Bearing, Many PlasticsBearing ChoicesBall, Needle, Sintered Bronze, PlasticWarranty6 months ~ 12 monthsSpecial Feature:1. good wear ... of machineTechnologycasting by handOur advantagewe have our own lather & grinding machine to make sure the precision can match our customers' needs ...