Shimano Deore XT BB-MT800 Bottom Bracket BSA$34
XT has gone 11-speed, and along with the number of gears, the bottom brackets are now also inspired by XTR. They have a decreased the bearing size to increase rolling efficiency and reduce weight. They are also better sealed to reject whatever muck the trails conjure up and throw at them.
• For Shimano 24mm MTB cranks
• High quality sealed bearings
• 68/73 mm shell width
• HOLLOWTECH II Technology