... carbon steel as C45, 20CrMnTi, 40Cr, 42CrMo, stainless steel, nylon Worm gear Material: carbon steel as C45, 20CrMnTi, 40Cr, 42CrMo, stainless steel ... ,20B9-114,24B9-90,28B9-76,32B9-76Heat Treatment: Hardening and Tempering, High Frequency Quenching, Carburizing QuenchingProcess: Investment casting, die ... http://dahaisprocket.preview.alibaba.comTel: +86-0317-2781695Skype: karensun20080811 Worm gear