Synchronous Pulley; 20MM Belt Width; 8 MM Belt Pitch; 8M-20 Belt Style; 21 Teeth; 28MM Face Width; Rough Bore; 52.1MM Outside Diameter; 53.47MM Pitch Diameter; No Keyway; No Bushing; Yes Minimum Plain Bore

Synchronous Pulley; 30MM Belt Width; 8 MM Belt Pitch; 8M-30 Belt Style; 21 Teeth; 38MM Face Width; Rough Bore; 52.1MM Outside Diameter; 53.47MM Pitch Diameter; No Keyway; No Bushing; Yes Minimum Plain Bore

Synchronous Pulley; 30MM Belt Width; 8 MM Belt Pitch; 8M-30 Belt Style; 21 Teeth; 38MM Face Width; Bushed; 52.1MM Outside Diameter; 53.47MM Pitch Diameter; Yes Keyway; 9 To 25MM Bushing Bore Range; 1008 Bushing; No Minimum Plain Bore