Security Boss 3-Sided Exterior Kennel DoorDescription Security Boss 3 Sided Exterior Professional Kennel Door Custom Made Energy Efficient Kennel Dog Door The 3 Sided Exterior Dog Kennel Door is an energy efficient exterior kennel door designed to cover the exterior of the kennel guillotine door to keep heat cool in the building and prevent bugs and dirt from entering. Featuring an energy efficient exterior kennel door model that features a heavy duty bi directional hinge connection to the