These insoles provide superior cushioning and a 44%* energy return. The dual-density design absorbs impact and shock where your feet need it most. Anatomical cushioning system features a dual-density gel that absorbs impact and shock where the foot needs it most. Spenco's Performance Thermoplastic Rubber (TPR) Gel combines superior cushioning and energy return for ultimate performance. Heel cupping provides extra cushioning and stability for the heel. Available in 6 sizes: offers correct arch placement for better overall fit, comfort, and performance. Low-friction top cloth helps reduce friction that causes blisters and calluses. Sold in pairs.