CMC CRANKS ISIS Using the same heat-treated crank arms as our CMC II and III's cranksets but using the industry standard ISIS splined BB format. You get the strength of a 4130 heat-treated cromoly crankset and the ease and simplicity of the ISIS fitting. The 4-bolt 104/64 3-ring compatible forged spider is attached via a pressure screw and circlipped securely in place for a rock solid connection. Go ahead, be brutal. Available in either classic black or powder white. (ISIS bottom bracket not included) Cromoly Monocoque Construction Cranks Material: 4130 heat treated cromoly Arm size: 175mm with ISIS compatibility Color: black / white