... , DIN, JIS 3.Material: According to customer's drawing Specifications:tooth shaft:Material: (20 Cr /40Cr) Heat treament: 1. Case harden ... 0.4-0.8 Accurancy: 8-7GB 1) Processing of tooth shaft: Precision forging, precision machining and roll forming 2) Heat ... treatment of tooth shaft: Carburizing 3) Very competitive prices and satisfactory service 4 ...