Wheels Manufacturing BB30 to Outboard Bottom Bracket with Shimano Compatible for Ceramic Bearings, Red Ceramic bearings; USA Machined shell is superior in function and durability to plastic Will accept current 24mm (Shimano, FSA, Race Face, etc.) cranks Enduro ABEC 3 sealed bearings. Dual silicone seal keeps the contamination out for longer life. Serviceable bearings Threaded design eliminates creaking Made in the USA