For Yamaha 660 Rhino 2004-2007 & Grizzly 660 YFM660F 02-08Main Functions: Increases horsepower & Increase lifespan & Reduces clutch slippageProduct Features:1. Brand New Wet Clutch Brass Slugs Kit , total 5 pcs2. Adding weight to the internal wet clutch causes the friction shoes to engage with more force3. Increases the holding power of the clutch shoes to the clutch drum, reduces wear caused by clutch slippage, maximize your vehicles acceleration and power4. Important Part for high horsepower engines, four-seaters, Duners, and mud guys with big tires5. Easy Installation, direct bolt on replacement6. Worldwide Fast Delivery & Long Time Warranty