This one-piece double wide shaft collar has a 1.Ruland clamp style shaft collars do not mar the shaft, are infinitely adjustable, and have superior holding power when compared to set screw collars.125", Stainless, OD 1 7/8" Tightly controlled face to bore perpendicularity is maintained (TIR of . Keyed Shaft Collar, 1pc Double Wide, Bore 1.