Constructed of light weight 6061T6 aluminum, the ALTA SC pulley body decreases rotational inertia of the supercharger adding response to your engine.
Holes are cross drilled through the pulley and over each groove, to increase belt grip and reduce belt slippage as your belt stretches. Also incorporated into the design are oversized belt retainers, which reduces belts from jumping off.
The black outer pulley is machined on a lathe from solid billet aluminum. Since this part is perfectly symmetrical it is naturally balanced in its self.
The non-symetrical hub adaptor must be balanced to offset the weight of the clamping bolts and slit. In the machine shop we balanced our prototype pulley to within 0.1 gram at 16000RPM (even better than stock). Data from that balancing was added to the model and applied to all production parts ensuring the entire part is balanced.