Praxis Works Alba M30 Solid Forged Crank Arm Set 110BCD 172.5 mm Matte Black. Condition is "Used". Shipped with USPS Priority Mail. Comes with 36T chainring only. 52T should be purchased separately, unless converted to a 1x. These cranks are suitable for Praxis M30 bottom brackets, which have a step-down 'GXP style' 30mm drive/28mm non-drive bearing. They are compatible with BSA, BB86, BB30/PF30 shells, but must have the M30 bottom bracket to accommodate the 30mm/28mm spindle. The Alba are quality cranks found on many comp-level builds.