; Extra long to accommodate any combination; Steel, self-centering mandrel bolts directly to harmonic balancer for dead-accurate concentricity; Pulleys are 6061-T6 aluminum and hard coat anodized for exceptional strength and extended service life; Includes: 2-1/2 V-belt pulley for vacuum pump, 1 (16-tooth) Gilmer pulley for external oil pump, guide plates, assorted spacers, belt guides & hardware; For optimum accessory speed, use with Moroso Dry Sump Gilmer Pulleys, and Vacuum Pump V-Belt Pulley No. 64885