1/2" thick cross-linked, high density, premium Exervo EVA foam interlocking mats * Infinitely expandable- add more sets to cover larger areas. Includes finish borders * Transform your floor in minutes- easy, low cost solution that"s easy to assemble * EVA foam is a warm comfortable surface with no odor. Impervious to sweat & moisture * ASTM F963-07 Flammability Tests- PASSED EN-71 Toxic Elements Analysis- PASSED