This is a A-801-1221 Spline Bore Implement Yoke (w/ 21/64" Pin Hole) PN: 801-1221Main Description As Following : A-801-1221 Spline Bore Implement Yoke (w/ 21/64" Pin Hole) PN: 801-1221 Found in Section & Models : Driveline > Driveline Components, Weasler Domestic: 12 Series, Driveline > Yokes, Weasler Domestic: 12 Series Associated Items : New Also This is An Aftermarket Product And : 12 Series Implement Splined Bore Yoke. 1-3/8" 21 spline with 21/64" pin hole. Original Weasler part. Bore: 1 3/8" - 21 Spl. Pin Hole: 21/64"