This is a A-PLW4 Pulley PN: PLW4Main Description As Following : A-PLW4 Pulley P.N: PLW4 This pulley can be used with either A or B width belts due to its dual groove / taper configuration.Hub Required: WOutside Diameter: 4" Crossed From: WSP400W , , 21020040 , , 21020040 , , 21020040 , , 2827-44027 JOHN DAY , 673-S85010400 , , 673S85010400 , Found in Section & Models : Chains/ Sprockets/ Pulleys/ Hubs > Pulleys, (Miscellaneous) (UNDEFINED): SEVERAL Associated Items : New Also This is An Aftermarket Product And : This pulley can be used with either A or B width belts due to its dual groove / taper configuration. Hub Required: W Outside Diameter: 4"