Pure Fix 700C 40mm Wheelset Aerodynamic, lightweight, double-walled aluminum set of front and rear 700C bicycle wheels with a 40mm rim depth Flip-flop hubs with pre-attached 16T fixed cog and 16T freewheel cog for single-speed riding 32 spokes each wheel Nylon rim-strips to protect against sharp edges and help prevent tube puncture Recommended for use with tires ranging from 23x700C to 32x700C (tires and tubes sold separately)