This is a A-110-5506 Auto-Lok Tractor Yoke PN: 110-5506Main Description As Following : A-110-5506 Auto-Lok Tractor Yoke PN: 110-5506 Found in Section & Models : Driveline > Yokes, Weasler Domestic: 55 Series Associated Items : A-13004000 Also This is An Aftermarket Product And : Original Weasler part. Bore: 1 3/8" - 6 Spl.