<br><b>This is a Brand New Aluminum Crankshaft Lower pulley. This is a Triple groove pulley designed for your Small Block Chevy with a Short Water Pump. This has a 6.6" Diameter. Constructed of thick gauge aluminum and with a high quality Satin Aluminum finish, this kit would be great addition to your project.</b><br> <br><b>Specification:</b><br> Pulley Diameter is 6 9/16"<br> Pulley is 2" Tall<br> Bolt Pattern is 2 3/4"<br> Center Hole is 1 1/8"<br> Machined From Billet Aluminium<br> These Feature deep grooves to prevent belts from slipping<br>