Bearing is packed with heavy duty premium marine grease and with the addition of special complex thickeners which allows it to be virtually waterproof Nitrile butadiene rubber double-lip oil seals help prevent abrasives, corrosive moisture and other harmful contaminants from entering bearings To further help keep any moisture out, we have gone from 30% grease filling to a 60% for harsh conditions The special v-groove on the inner race is better for resistance to water intrusion Provides unsurpassed rust and corrosion protection Factory-Links ball bearings are specially designed for Off-Road use. - Yamaha YXR 450F Rhino 4x4 (2006, 2008, 2007, 2009); Yamaha YXR 660F Rhino 4x4 (2005, 2006, 2004, 2007); Yamaha Rhino 450 Special Edition (2007, 2008); Yamaha YXR Rhino 700 Special Edition (2009, 2008, 2013); Yamaha Rhino 660 Special Edition (2006, 2007); Yamaha YXR 700FI Rhino 4x4 (2010, 2011, 2012, 2009, 2008, 2013); Yamaha YXR Rhino 700 Sport (2008, 2009, 2012, 2011); Yamaha Rhino 660 Exploring Edition (2006, 2007); Yamaha Rhino 700 Ducks Unlimited Edition (2008, 2009); Yamaha Rhino 660 Ducks Unlimited Edition (2007); Yamaha Rhino 660 Sport Edition (2007)