【MAXIMUM FREEDOM FOR PETS】MAVRICFLEX heavy-duty dog door is made of the best aerospace-grade aluminum alloy, which provides exceptional strength and durability. Compared to regular aluminum alloy, the MAVRICFLEX heavy-duty dog door is heavier and thicker, capable of withstanding greater pressure and impact. Whether it's a large breed or an active small breed, our dog doors can withstand their coming and going, ensuring a long-lasting lifespan! 【DIMENSION & TELESCOPING WIDTH】Mavricflex aluminum dog door frame size is 14 3/8''(W) x 20 3/8''(H), Cutting size is 12 5/8''(W) x 18 1/2''(H), Flap opening is 11 1/8”(W) x 16 3/8''(H). It fits paneled, wood, PVC, and metal doors1 1 /4'' - 2 1/2'' thick, and is designed for pets up to 100 pounds. 【Sturdy & Energy-Saving】All MAVRICFLEX dog doors undergo rigorous quality control and craftsmanship inspection to ensure their excellent sealing. The soft flap version has been tested multiple times to ensure that the flip part is solid and reliable, and will not easily come off. In addition, the soft flap is designed with strong magnets, allowing it to fully adhere to the frame without leaving any gaps. Even a gentle breeze won't easily blow it open, greatly improving energy efficiency !