Compression molded composite crankarms. Monocoque crankarm and spider. Oversize splined integrated chromoly bottom bracket axle. Precision 100% CNC machined 7075/T6 chainrings. AL7075 Torx T-30 alloy chainring bolts. Aluminum MegaExo oversize cartridge bearing bottom bracket cups. 24mm spindle. 130mm bolt circle. 53/39 chainrings.