This is a A-800-3520 Round Bore Implement Yoke (w/ Keyway & Set Screw) PN: 800-3520Main Description As Following : A-800-3520 Round Bore Implement Yoke (w/ Keyway & Set Screw) PN: 800-3520 Found in Section & Models : Driveline > Driveline Components, Weasler Domestic: 35 Series, Driveline > Yokes, Weasler Domestic: 35 Series Associated Items : New Also This is An Aftermarket Product And : 35 Series implement yoke. 1-1/4" round bore with 1/4" standard keyway and set screw. Original Weasler part. Bore: 1 1/4" Standard Keyway: 1/4"