1. The frame is made of ABS material fixed by screw to prevent from coming off. It is easy to install 2. Closure style inner frame for easy installation. The product is solid and durable to ensure that the pets can go in or out freely 3. Adopting magnet automatic closure mode, it will be close automatically when the pet left from it. 4. Closure type lock catch design for effectively preventing the pet from running out randomly 5. Application: for cats and small / medium / large dogs, also for all doors, windows, panels or any other screen area 6.Size(approx.): frame size: 42 * 37cm / 16.54 * 14.57in, thickness: 1.5cm / 0.59in, inner frame size: 36 * 31cm / 14.17 * 12.20in. Please refer to the size table for details. 7. Features: it is vermin proof with smooth surface; of fine material, even texture, stable structure. Not easy to deform; made of high-intensity MDF which is of heat retaining, heat insulation and ageing resistant property.