Tightly controlled face to bore perpendicularity is maintained (TIR of
Balanced Collar, 1pc Clamp, Balanced, Bore 48mm, 303 Stainless Steel This two-piece shaft collar has a 48mm bore, 78mm OD, and 19mm width. It has a balanced design for better performance in high RPM applications. Ruland clamp style shaft collars do not mar the shaft, are infinitely adjustable, and have superior holding power when compared to set screw collars..