Our booster seats are made from a dense foam with a removable micro suede 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 Medium Booster measures 18” wide x 15.5” deep x 13.5” high and can hold pets up to 15 lbs.Free Shipping in the 48 contiguous states. Shipping charges will apply on orders to AK, HI, US territories.