Chicago Die Casting 1/2" Bore x 1-3/4" Diameter Single V-Groove Die Cast Pulley is designed for use with 4L or 1/2" x 11/32" belts. It has a hollow head set screw for secure attachment. This pulley is made of die cast metal for durability and long-lasting performance. It is commonly used in various industrial and automotive applications where power transmission is required.