This item fits the following applications:  Yamaha rhino 450 550 660 and 700  Yamaha grizzly 450 550 600 660 and 700GET YOUR POWER BACK WITH THIS COMPLETE KIT!!!3 kits to choose from designed for machines with 25-27" tires, 28-30"tires, and 31-32" tiresKit features new secondary spring and primary clutch modsHelps restore power loss due to addition of larger tiresAllows for easier turning of larger tires in the mudBetter low end power and torqueQuicker backshift which results in crisp throttle responseReduces belt slip and clutchInstallation is recommended by a professional mechanic.These kits have been tested tough!We run these kits on all our bikes and have no problem turning large tires.