Woodstock W1111 1-1/4-Inch by 1/2-Inch Rub Collar Bore 1-1/4-Inch outside diameter by 1/2-Inch inside diameter All Woodstock rub collars are manufacutred from solid steel on CNC lathes These Rub Collars are assembled in the U.S.A using high-quality, maintenenace-free bearing