Sold as a 2-pack, this rear spring U-bolt kit fits Mack applications and measures 4 in. inside width by 19-1/2 in. inside length, with a 3-1/2 in. thread length and 1-1/4in-12 thread size. Each kit’s semi-round bolt shape conforms to the axle housing contour to clamp the leaf spring in place, and comes complete with matching washers and nuts for installation. This kit is built as a replacement for Mack suspension assemblies.Interchanges:251642997QK3145P6Mack 7QK3148P6This unit is sold in packs of 2.FeaturesSemi-round U-bolt kit for rear spring applicationsSold as a 2-pack4 in. inside width19-1/2 in. inside length3-1/2 in. thread length, 1-1/4in-12 threadIncludes matching washer and nut per kitTech SpecsInside Width: 4 in.Inside Length: 19-1/2 in.Thread Length: 3-1/2 in.Thread Size: 1-1/4in-12Kit Contents: U-bolt, washer, nut