The new R7100 crankset is improved over the old one and has taken the best of the old 105 crankset, along with the best of the Ultegra crankset, and combined it.

172.5mm pedal arm.

Two blades of 50 and 34 teeth.

Fits both external bearings and pressfit bearings with a 24 mm hole, e.g. from Shimano.