This is a panel cat door for sash installation designed to prevent stray cats from entering. It is suitable for regular-sized cats. Only cats wearing the dedicated magnetic key can enter the house from the outside, thus preventing stray cats from entering. The cat door is a Catmate 254. ★Only one unit available. First come, first served. ● Compatible with sash heights of 150 cm to 230 cm [Made in Japan] ● Adjust the height by inserting the upper panel into the main panel. ● Cat entrance/exit: 14.5 cm x 14.5 cm *Please be sure to check if your cat can pass through. ● Sensor door is already installed. ● Comes with 2 sensor magnetic keys. ● Please purchase a square 9V battery. Returns and cancellations are not accepted.