Saco Billet Stock Size Pulleys are Billet Aluminum and feature a chromoly center hub. Pulley is hard black anodized for wear, and have numbers and timing marks laser engraved. All Saco crank pulleys come with sand seal. Requires the use of a longer pulley bolt, part number 30-1132. (Note: If used with non-machined case, you must use part number 30-1126 also)