4.Outside Diameter: 55mm-150mm 5.Specifications(mm): Module OutsideDia.OverallLengthHoleDia.1.255040221.555451.75255502.25602.565552.7537060273.2575653.575703.758070480754.2585804.58585590905.5100953261051006.511010071151058125115 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.