Endura Flap Pet Door

This door’s flexible yet durable flap has a strong magnetic seal that stays closed in temperature extremes and in windy conditions. Unlike nylon, which can become stiff and brittle in freezing temperatures, the Endura Flap is made of a special polymer, designed to remain flexible to 40 below zero. A double-flap option keeps heat in under more extreme climate conditions. The insulated flap swings on a stainless steel rod, eliminating the wear caused by flexing. Its taller, less-square dimensions allow lower mounting, so your dog doesn’t have to step as high to get in and out.

• Self-framing door mounts: $149 to $249 (single flap), $259 to $399 (double flap); from Patio Pacific Inc.; (800) 826-2871; www.petdoors.com