Waterproof liner pet bed mattress protects against accidents, enough filling on bottom for extreme support and comfort. Fleece Upgrade Design. Keep warm all year a square for pet dogs or cats, pet bed mat will always keep its shape and will not flatten over time.6 sizes suit for small to large pets. S: 16.93"12.6",0.77lbs,suit for less 6.6lbs.M: 21.26"*16.54",1.21Lbs,suit for less 22Lbs.L: 30.75"*19.7",1.65lbs,suit for less 33lbs . XL:31.5"*23.6",2.2lbs,suit for less 55lbs pets.XXL:37.4"*28.35",2.97lbs,suit for less 61.6lbs. 3XL :43.3*32.3",3.74lbs,suit for less 77lbs .