The used tough synthetic leathers provide great protection and excellent durability. The SH-XC31 has a "Cross X"-strap that is optimized for relieving tension on top of foot during push off motion. Shimano's Dynalast provides a precise fit and improves pedaling efficiency. So the shoe features a XC race specific outsole that is lightweight, ultra-stiff and combined with a lower stack height for providing superior energy transfer and efficiency. Moreover the sole has mud-shedding polyurethane lugs with spikes. At a last point the SH-XC31 offers an glass fiber reinforced sole. Shimano recommends the use with PD-M520 pedals.