Welcome Coir Doormat by Castle Mats, Size 18 x 30 inches, Non-Slip, Durable, Made Using Odor-Free Natural Fibers GREAT FOR INDOOR AND OUTDOOR USE: This 17 x 29 inch doormat, 1/2 inch thick, contains a waterproof rubber backing that is gentle on indoor flooring, while its weather-resistant fiber top is great for outside use