.carbon steel gear.forged and hardened.middle carbon steel plate shaft.abs enclosure.blow mould case packedsize:1/4*5/16",3/8* 7/16", 1/2*9/16",5/8"*11/16" 3/4"*7/8"or 6*8, 9*10, 12*13, 15*17, 19*22mm .blow mould case packed