BKS-5428 - stainless steel, Angular Contact, Bottom Bracket Bearing Kit for Shimano 24mm Cranksets and Trek BB90/95 framesets This kit includes two 440C stainless steel, Angular-Contact bearings along with all of the necessary seals and spacers to complete a precise, professional installation. Enduro Angular Contact, 440C stainless steel balls and races provide long life and superior corrosion resistance in applications and environments that may be less than ideal. Though stainless steel has 20% less load capacity and is slightly softer than our standard 52100 chromium steel used in most of our bearings, stainless steel is an excellent alternative for use in wet conditions, if you wash your bike often, or where sweat can be a problem. Enduro Bearings also uses LLB type seals and CRC Marine Grease in these bearings to additionally water proof against the elements. Enduro stainless bearings all carry a full two-year anti-corrosion warranty. For the easiest removal and installation of this bearing kit, we recommend the BRT-003 24m x 37mm bearing tool. BRT-003 allows you to quickly remove and install bearings with a few twists of the wrist The Enduro line of bearings are available in high-carbon chromium steel, 440C stainless steel, ceramic-hybrid and XD15 with ceramic or stainless balls. Our bearings are always engineered with deepest groove races possible to accommodate the largest balls and feature dual-lip seals that ride in a micro-groove creating a full labyrinth to provide superior protection against the elements.