Columns of shock absorbing cells duplicate and enhance nature's own shock absorbing design. Tuli'sare worn as an insert in the heels of your shoes where shock absorption is needed. Provides lightweight protection for the everyday pain of heel strike. Tuli'spatented multi-cell, multi-layer "waffle" design absorbs shock and returns impact energy just like the system naturally found in your feet. Upon impact, Tuli'swaffle design collapses and even rotates with the normal motion of your foot to absorb the shock of walking and running. And just like a spring, Tuli'sClassic Heel Cups returns that energy back for maximum performance. Each box contains one pair of heel cups.