Upgrade hinge,More sturdy and more safe: Our first consideration in any situation is the safety of our pets.The upgraded hinge is stronger and not easy to fall off.Plastic support can be damaged or broken over time.That's why we chose to use metal supports for our windowsill cat perch bottom support. When installed our products and metal support will support pets up to 35 lbs. If you choose not to install a bracket and only use Velcro, we recommend it for pets weighing up to 20 pounds..Select installation method as needed: Topmart cat perch shelf have two installation methods.One is Velcro, you only need to tear the tape to paste it, the operation is very simple, it can bear 20 pounds. The other is a screw connection. You need to punch the holes and install the screws. The advantage is that it can bear 35 pounds. You can choose the right method depending on the usage..Comfort and Stability:Foam cushion size: 23.6" X 12" X 1.2" ( L x W x H ).The wider cushion allows your pet to lie on it in any position without worrying about falling.Thicker cushions provide a softer touch, and your pet will feel relaxed and comfortable on it..Enjoy the sun and the view:When the temperature is too low in winter, the cat lying on the sofa or bed often feels cold because it cannot get the sun, but lying on our cat’s window sill can enjoy the sun all day. This is a perfect window seat for cats with a great view of nature..Easy to clean and store:Removable, machine washable cover allows you to keep your pet clean at all times.Foldable bottom plate will take up less storage space. Note:The minimum length of the window sill is 4 inches.