... Gear Hobs Milling Cutter: 1.Module: m1-m40 2.ClassAA , ClassA , ClassB 3.Single thread and right hand 4.Material: HSS HSS Gear Hobs Milling Cutter ... :1.Gear hobs,spline hobs,standard gear hobs,sprocket hobs,worm gear hobs, serration hobs,timing pulley ...