This is a A-580-7606 Overrunning Clutch, W2400 Series, 1 3/8" X 6 Spline W/ Slide Lock PN: 580-7606Main Description As Following : A-580-7606 Overrunning Clutch, W2400 Series, 1 3/8" X 6 Spline W/ Slide Lock PN: 580-7606 Found in Section & Models : Driveline > Clutch, Walterscheid TORQMASTER: 2400 SERIES Associated Items : New Also This is An Aftermarket Product And : Weasler alternative to original part.