The M30 bottom bracket family is for the Praxis M30 spindle based cranks. The M30 spindles are 30mm and then have a step-down to 28mm to lock on the Non Drive bearing. These use a drive side wave-washer for the bearing preload, and a 30MM Drive bearing with a step down to 28MM Non Drive bearing. The Zayante, Alba, Girder and Cadet all use the Praxis M30 bottom bracket.
