This is the replacement derailleur hanger for the BMC Racemaster SLX 01 road frame. It's always great to have one of these on hand to keep your shifting as smooth as possible. You never know when your bike might get blown over in the parking lot while you're tugging on your chamois shorts in the front seat. Of course, crashes take their toll on these little parts as well. It comes with two fasteners and installs in a few minutes.