ACB 6808 CC BO - 1-1/2 Black-Oxide treated Angular Contact Headset Bearing (40x52x6.5-36/45) 428420 Machined and ground entirely from

Machined and ground entirely from 440C stainless steel

as bottom bracket bearing for some older square taper BBs

Radial Suspension Bearing - 12mm x 21mm 5mm

ABEC-5 Bottom Bracket Bearing Kit for Shimano 24mm cranksets and BB86/92 cups

which even covers wear and corrosion (the most common source of eventual failure)

ACB 6808 CC BO - 1-1/2 Black-Oxide treated Angular Contact Headset Bearing (40x52x6.5-36/45) 428420 Machined and ground entirely fromACB 6808 CC 1 1 2 Angular Contact Black Oxide treated Headset bearing (40mm x 52mm x 6. 5mm; 36 x 45deg) Angular contact headset bearing featuring anti corrosion Black Oxide Magnetite treated 52100 High Carbon Chromium alloy races paired with grade 10 Balls. Black Oxide treatment provides an extra level of corrosion resistance and extended worry free performance. This size bearing is also known in the bike Industry by these part numbers: HD 1404K