This is a A-800-0610 Round Bore Implement Yoke (w/ Keyway & Set Screw) PN: 800-0610Main Description As Following : A-800-0610 Round Bore Implement Yoke (w/ Keyway & Set Screw) PN: 800-0610 Found in Section & Models : Driveline > Driveline Components, Weasler Domestic: 6 SERIES, Driveline > Yokes, Weasler Domestic: 6 SERIES Associated Items : New Also This is An Aftermarket Product And : Implement yoke with round bore. Yoke has a 5/8" round bore with 3/16" standard keyway and set screw. Original Weasler part. Bore: 5/8" Standard Keyway: 3/16"