HDK-0010 - 1-1/8" x 1-1/2" Stainless Steel, Angle Contact, Zero-Stack Headset Bearing Kit for 44mm/56mm ID head tube framesets. MAXhit is the latest patented innovation from Enduro, where the bearing is the central component. MAXhit headset bearings are designed to fit directly into your bike's head tube, eliminating the need for the aluminum cups traditionally used to house bearings. This unique design allows for much larger balls, effectively doubling the load capacity compared to standard headset bearings. The kit includes a crown race, an upper spacer, and an upper bearing cap. The Maxhit headset bearings are made entirely from 440C stainless steel and come with a lifetime warranty. They feature exclusive double-lip labyrinth seals and Enduro's extra high-pressure grease to ensure hassle-free, long-lasting performance. Enduro's headset bearings start with chrome-plated steel, Black Oxide Type A/C finish, and then provide complete 440C stainless steel at the top. They are always designed with the largest possible balls and double-lip seals in a micron groove for ultimate protection against moisture and the elements. They are filled 90% with waterproof high-pressure grease, so you never have to wonder if there is grease inside. Enduro's angular contact (A/C) bearings ensure that all balls are engaged to distribute the load over a larger area, squeezing out water and minimizing wear.