The ACB 3645 3344 SS is a 1-1/8" angular-contact headset bearing measuring 33mm x 44mm x 6mm with a 36x45 degree angle. It is engineered with 440C stainless steel balls and races to provide superior corrosion protection in environments where moisture, sweat, and electrolyte drinks are a constant factor.

High-Carbon 440C Stainless Steel: Enduro utilizes 440C stainless steel, the highest strength and hardness alloy of the 440-series. The balls and races undergo special heat and cryogenic treatments to achieve maximum wear resistance and long-term durability in less-than-ideal riding conditions.

Angular Contact Precision: Designed as an Angular Contact (A/C) bearing, this model ensures that all balls are evenly engaged. This spreads forces over a larger surface area to minimize wear and extend the life of your headset assembly.

Ultimate Waterproofing: Features LLB-type dual-lip seals that ride in a micro-groove labyrinth to block contaminants. The bearing is 90% filled with high-pressure Almagard 3752 waterproof grease for maximum protection against the elements.

Industry Cross-Compatibility: This bearing is commonly used across the bike industry and is also known by part numbers ACB3344H6 and AC3344. It is the same high-specification bearing found in many premium headset brands that carry lifetime warranties.