Dog Mate Multi Insulation Dog Door - WhiteDog Mate Dog Doors are suitable for a wide range of dog breeds. The medium and large doors feature robust 2 way locking panels for security. All flaps are fully brush sealed with magnetic closure for total weatherproofing and minimum energy loss from the house. For dogs up to 18" shoulder height Self lining to 2" thick ideal for all doors and walls Robust 2 way locking security panel Silent action weatherproof flap with vision panel Lightweight flap