EXOspikes Concave Tungsten Carbide Spikes - Up to 100 times more abrasion resistant than steel, tungsten carbide spikes withstand prolonged use on mixed terrain and roads. Concave spikes deliver instant engagement on glare ice. Flexible TPU Traction Matrix - Twelve strategically placed 0.29" tungsten carbide spikes are integrated into a tough traction matrix that's abrasion-resistant, lightweight and adapts to uneven terrain. Ergonomically Shaped Thermoplastic Elastomer (TPE) Harness - Features patented reinforced eyelets for increased durability, attaches securely to a variety of footwear and retains its elasticity down to -22°F (-30°C). Integrated Toe Bail - Keeps the toe from pushing through the front of the harness for added security while descending. Raised Heel Tab - Provides a secure grip point on the harness for easy on and off in frozen winter conditions with cold or gloved hands.