Security Boss Classic Guillotine Kennel DoorThe Classic Kennel Door is a HDPE panel that is reinforced on all sides with the Security Boss custom C channel. This reinforcement prevents warping, bending and binding that naturally occurs with all polypropylene, plastic or HDPE type kennel doors. The Classic Kennel Door will maintain its integrity due to the strong aluminum framing on all sides. All Security Boss products are hand built to order. Know Before You BuyHDPE, polypropylene and plastic