POWERBOND RACE PERFORMANCE 25% UNDERDRIVE BALANCER TO SUIT HSV GRANGE WM WN LS2 LS3 6.0L 6.2L V8The Powerbond 25% Underdrive balancer produces more horsepower by reducing the parasitic power loss from driving engine accessories including alternator, air conditioning, water pump and power steering at high engine RPMs. This small and light weight harmonic balancer performs like a light flywheel which sharpens throttle response and allows the engine to rev out faster. Specifications: Type: 4PK 6PK Contents: 1 X Race performance 25% underdrive