Entrance/Scrapper-Wipper for Indoor and Outdoor use. Earth Friendly" 100% Nitrile flat backing made with 24 oz.sq/yd solution-dyed polypropylene fabric is highly stain resistant. 3/8" thick bi-level surface effectively removes and stores dirt and moisture beneath shoe level between cleanings. Unique "Water Dam" allows the Waterhog mat to hold up to 1 1/2 gallons of water per square yard, water and dirt stay on the mat. Anti-Static.