Callista76. Phenomenal grip: using more tungsten carbide spikes than ever before, maximum grip is guaranteed. Spikes carefully positioned to ensure grip when racing at speed, no matter what part of the foot strikes the ground Precision fit Run with protection and comfort: protect-shank aligns with spikes underneath to protect foot's metatarsals, while still allowing for a flexible ride Durability: full welded rand ensures 360-degree protection and ensures minor bumps won't end the day early.