Give your cat the freedom to come and go as it pleases with this cat flap featuring a 4-way locking system. Slide the locks on the bottom of the flap to set the door to one of the following options: Cat can only enter from the outside but cannot come out Cat can exit but cannot enter (to prevent other cats from entering) also enter) The flap is locked on both sides The flap is completely open and the cat can come and go at will The cat flap is easy to install and is suitable for n any wall or door up to 50mm thick. Also suitable for small dogs/cats. < p>Features: Size: S:1919.72cm M:1919.75.3cm L:2523.55.3cm XL :255.527.7cm(please measure your pet before ordering!) The pet flap at 4 way is new and boxed Material: hard plastic installation method: Tools needed: electric drill, iron saw or electric saw, measuring ruler; Step 1: use a piece of paper first to draw the size of the door cover (there may be a few millimeters error); Step 2: Finish the drawing and mark it on the