Enduro Sealed Angular Contact Headset Bearing 3645 3748 BO - 1 3/8" - 37 x 48 x 6.5mm (36 x 45 deg)

ACB 3645 3748 BO - 1 3/8" Black-Oxide, Angular-Contact Headset Bearing - 37 x 48 x 6.5mm (36 x 45 deg)

The angular-contact headset bearing showcases anti-corrosion Black Oxide/Magnetite-coated 52100 High-Carbon Chromium alloy races paired with grade 10 Balls, delivering enhanced corrosion resistance and prolonged performance.

Recognized in the bike industry as part number Ai-70, this bearing size is well-known.

The Enduro series of angular-contact headset bearings begins with Chromium steel races treated with Black Oxide, progresses to full 440C stainless steel, and culminates in the top-tier XD-15 aerospace-stainless (both races and balls), backed by a lifetime guarantee. These bearings are consistently designed with the largest feasible balls, incorporate dual-lip seals moving within micro-grooves (labyrinth), and are filled to 90% capacity with high-pressure waterproof grease, ensuring optimal protection against sweat and environmental elements. The Enduro Angular Contact (A/C) bearings are crafted to ensure uniform engagement of all balls, distributing force across a larger surface area, thus reducing friction, minimizing wear, and extending the bearing's lifespan.