Cast Iron 4.75" 2 Groove Dual Belt B Section 5L Pulley w/ 1-3/8" Sheave Bushing Masterdrive dual groove 4.75" cast iron pulley/sheave with 1-3/8" H bushing. This is a high-quality 2-piece pulley that measures 4.75" outside diameter and is designed to be used with an H style bushing. The 1-3/8" bushing (included) inserts into the center of the pulley and slides over the shaft. As you tighten down the bolts on the H bushing it will tighten down on the shaft making this style of pulley much more secure than a standard single-piece pulley. This listing includes an H bushing to fit on a 1-3/8" shaft. The bushing is made of solid steel and precision machined to ensure high quality and secure attachment to your motor/engine shaft. This pulley accepts B Section also known as 5L series belts. These belts are 5/8" wide. This pulley will work with A Section belts, also known as 4L; however, they will sit farther down in the groove, reducing your pulley size by 1/4" to 1/2" on average, depending on the size of the pulley. Specifications: Dual Groove Pulley 1-3/8" Bushing Included Accepts: B Section / 5L Section Belts High-Quality Cast Iron Construction Solid Steel Bushing For Use on 1-3/8" Shaft Outside Diameter of Pulley: 4.75"