Dog Gone Smart Large Dirty Dog Doormat Our mats have a GSM abosrption rate of 3000 that is higher than our competitors with a GSM from 900 to 1500 The only mats to use the heavy "Gripper Non-Skid" backing on the bottom to prevent skidding and movement Constructed with double basting and even stitching for rugged durability and long lasting use The microfiber strands dry five times faster than ordinary doormats Large doormat measures 35 x 26 inches and is machine washable