These mats are recommended as an indoor mat, but substitutes as an outdoor mat in warm to moderate climates. The bi-level construction allows dirt and debris to get trapped below the walking surface and off your floors. The polypropylene carpeted surface makes this a scraper to remove debris and also a wiper to help trap moisture. The non-slip all-rubber cleated backing provides a secure gripping action to carpets and hard surface floors. The beveled edge border helps contain the dirt and moisture and helps reduce the chance of slips, trips and falls. Easy-to-clean and maintain—just shake out, vacuum, hose and dry or clean with a light carpet cleaning machine.