Achieves peak rpm faster and more aggressively Amazing all-around performance gains Holds peak rpm better Back shifts much quicker Superior weight profile offers better acceleration Works well with stock or modified motors Easily adjustable for tire size or other modifications Custom angle cut helix Much better power transfer than the stock weights Comes with two washers to prevent spring bind and free up clutch movement for faster shifts Spring holds much better tension on the belt than factory Includes primary and secondary springs Stage 1 or Stage 2 kits available Includes Goldstar weights. CLUTCH KIT XPT STG2