3.Pressure Angle(α): 14.5°- 30° 4.Helix Angle(β): 0°- 45° 5.Direction: Left Hand/Right Hand 6.Accuracy: GB/T6082-2001 Standard Class AA/A/B 7.Coating: TiN/TiAlN We can provide all kinds of gear hobs, gear shaper cutters and gear shaving cutters. If you have any requirement, pls contact us. We'll try our best to satisfy you. You're welcome every time, all the time.