Wolf Tooth Premium headsets feature high-end bearings made by Enduro. They are engineered to use the largest possible ball size and are filled with high-pressure waterproof lubricant. A pair of dual-lip seals ride in micro-grooves to keep out water and debris. - Stainless Steel Bearings provide unparalleled corrosion resistance - Highly recommended if your headset will be exposed to wet conditions or sweat - Lifetime warranty - Lower Bearing, includes race