DOP78-065CC Cub Cadet Idler Pulley Kit No. 753-08171. This is a quality aftermarket part. Inside Diameter 3/8, Outside diameter 4 7/8, width is 1" Replaces MTD part numbers 753-08171, 756-04129, 753-08068, 756-04129B, 753-04129C and Toro part number 112-0314.