Security Boss MaxSeal Hinged Replacement FlapsDescription Security Boss MaxSeal Hinged Replacement Flaps The MaxSeal Hinge Replacement Flap features a heavy duty hinge flap connection. This hinged flap design allows the flap to travel freely without a pinch point. This means your flaps will last longer in situations of heavy use or if the installed pet door is too low and the pet is hitting the flap connection. Note: It is very important to install any vinyl flap pet door at least 2" higher than