Check the listing for details. Spenco Polysorb Cross Trainer Athletic Cushioning Arch Support Insole System. Condition: New with tags. Listed at 24.95 USD. Spenco Polysorb Cross Trainer Athletic Cushioning Arch Support Insole System Spenco Polysorb Cross Trainer Cushioning Insoles provide the best combination of shock absorption and energy-return. This powerful duo works together to provide lasting comfort, help prevent injury and relieve foot pain. Our proven cushioning and support improves athletic performance and prolongs the life of your shoes. Ideal for running, walking, training and sports. About this item Spenco insoles with 4-way stretch fabric help prevent blisters EVA forefoot cushion provides cushioning and energy return for high impact sports Spencore material a 5/32 inch layer of this material absorbs shock and impact to provide our most intense comfort and cushioning Lightweight polysorb polyurethane foam provides arch and heel support Spencore heel plug provides extra cushioning and shock absorption in the heel