The Promax EX-2 external bottom bracket suits 30mm spindle cranks, like those found on the . 

The benefit of external bearings is to create a larger bearing that can cope with the pressure that is placed through them by higher loads and torque.

• Strong, stiff and lightweight forged and CNC machined aluminum cups
• Dual-lip labyrinth low-friction seals keep elements out without affecting pedal efficiency
• Custom sealed bearings are smooth and long lasting
• For use with 30mm diameter crank spindles such as RaceFace/Easton CINCH / Promax CK-1 cranks
• BB Shell Width: 68 , 73mm
• Bottom Bracket Shell I.D.: 1.37
• BB/Frame Interface: English (Threaded)
• Weight: 105 grams