Uncovered Medium 1 Pair Dual Durometer For Maximum Comfort While Standing Walking Or Running Medium-durometer Silicone In Main Body Effectively Absorbs Impact And Recovers Quickly Softer Silicone Blue Dot Under Heel Center Maximizes Shock Absorption And Comfort At Point Of Impact Washable And Reusable Retains Shape Will Not Deform Or Degrade With Use Optional Anti-microbial Cover Absorbs Odor Prevents Bacterial Growth And Allows The Foot And Insert To Slide Easily Into The Shoe