The individual exercise and rest mat are non-folding for seamless surface. The 2" thick EnviroSafe foam mats are covered by an 18 oz. tough fire-retardant phthalate-free PVC coated vinyl. The cover is sewn around foam. The EnviroSafe foam mats are eco-friendly. They are 100% toxin free, zero VOC's or off gas, hypoallergenic, latex-free, mold and mildew proof; 100% recyclable with no leaching chemicals. Medium firmness. Specify color.