Pearl iZUMi Women's Syncro Float IV Running Shoe 100% Synthetic and mesh Synthetic sole Heel measures approximately 1.5" 1:1 Seamless Upper creates an unparalleled fit with a seam-free interior 1:1 360 degree Lacing anatomically conforms to the foot for a tailored fit regardless of foot shape 1:1 Energy Foam cushions the forefoot upon impact and then returns energy back to the runner Half-length low-profile syncro Stability Frame SKYDEX heel crash pad