Our booster seats are made from a dense foam with a removable microsuede cover that is machine washable. A 2” thick pillow helps to keep pets comfortable. An adjustable tether secures pet in booster. Secures with vehicles safety belt system. The Large Booster measures 22.5” wide x 17.5” deep x 13.5” high and can hold up to 2 pets total of 25 Lbs.