Raised nubs remove dirt and moisture from shoes and trap it below foot level; water dam border holds up to 1.5 gallons of water per square yard, keeping your floors clean, dry and safe. Eco-friendly PET fabric (30 oz./sq yd) is made from 100% post-consumer recycled plastic from drink bottles, and SBR rubber backing contains 20% recycled rubber from car tires. Certified high-traction by the National Floor Safety Institute (NFSI). Fade and stain resistant solution-dyed PET fabric is resistant to staining, dries quickly, and will not fade or rot.