This high performance cross trainer features Tailex lining, F2 Dual Density Polyurethane Cushion Insert with TPU Heel Stabilizer and Shock Eliminator Heel Cushion insole, a Dual Density; Non-Marking Rubber Bottom and EVA CUshion Midsole with Wrap Around Shank Stabilizer; Heel Airbag and is 100% Non-Metallic. Stop pain and fatigue in their tracks with our new F2 FootForce insole. Compatible with both ESD and conductive footwear, F2 insoles cushion your feet and stabilize your heels to keep leg and back pain at bay for hours. Also features a composite toe cap which is made from a non-ferrous elastomeric material. This material is also light weight and will not conduct heat or electricity. Composite toes meet or exceed ASTM F2413-05 Standard for protective footwear.