; Fits Moroso Racing Vacuum Pumps or similar smog pumps that use OE-style, 3-bolt mounting pattern; Precision machined from the highest grade aircraft aluminum and hard-coat anodized for extended service life; Deep V-groove ensures belt retention under all racing conditions; Machined with six holes to reduce weight; 5 diameter pulley uses stock (3-bolt) mounting pattern with 1.16 bolt circle; Use with Moroso Vacuum Pump Nos. 22640, 22641, 22642, 22644, 22840, 22842 and 22843