... own needs like voltage, speed, torque front shaft length and so on. Model No.RS-385SA-3521RBRated voltage10.5VDCNo ... magnet3, 5, 7, 8, 9, 12,16 slots armatureSilicon-steel lamination with epoxy coatingHigh-carbon steel shaftCu-Ag alloy commutatorCopper-graphite brushesBe ... wire-40oC ~ 220oC bearing lubricantNeodymium magnets dc motor with 10.5v,high rpm electrical motor, used for air pump motor