21MM Belt Width; 8MM Belt Pitch; 8M-21 Poly Chain GT2 Belt Style; 27 Teeth; 23.368MM Face Width; Bushed; 81.458MM Flange OD; 67.158MM OD; 68.758MM Pitch Diam; Keyway; 12.7 To 28.575MM Bushing Bore Range; 1108 Bushing; No Minimum Plain Bore