"This Phoenix 5in. V Idler Pulley Wheel with 5/8in. bore offers smooth operation, high speed performance and long life. U.S.A. Bore Diameter in. 5/8, Part Type Pulleys, Pulley Diameter in. 5, Product Style V idler pulley, Compatible With Outdoor power equipment. 5/8in. bore idlers can be reduced to 3/8in. or 1/2in. with bushings Precision ground bearings with double seals protect against dirt and moisture for high speeds and long life"