Caster; Swivel; 8 x 3; Heavy Duty PolyU on Cast (Gr/Blk); Plate (6-1/4x7-1/2: holes: 4-1/8x6 slotted to 4-1/2x6-1/8; 1/2 bolt); Roller Brng; 3500#; Kingpinless (Item #66598)