This is a A-CA550R CA550-R Roller Link PN: CA550RMain Description As Following : A-CA550R CA550-R Roller Link P.N: CA550R Replaces: K39M Crossed From: CA550RL , , K39M MISCELLANEOUS , 042-CA550RL , Found in Section & Models : Chains/ Sprockets/ Pulleys/ Hubs > Roller Chains and Attachment Links, (Miscellaneous) (UNDEFINED): SEVERAL, Miscellaneous > Miscellaneous, (Miscellaneous) COMBINE: SEVERAL (CA550 Feeder Chain Attachment Connector) Associated Items : New Also This is An Aftermarket Product And : Replaces: K39M