For color choices, see Alternate Images Provide your kitty a comfortable lounging spot where he can enjoy the beautiful outdoors. Our Small Padded Cat Window Perch Features 1-inch thick foam for extra comfort. Attractive carpeted supports adjust to fit snuggly to most windows without tools. Size: One support 12-1/2w x 16-1/2 before carpeting. Window opening should be 18 minimum Works on most Sliding and Double Hung windows -- This window perches does not attach to the wall. There are 2 clips at the back of the perch that go into the track of the window, and a sliding wood/carpeted support underneath the moves toward the wall to lock the perch in place thru opposing pressure. It will not work on a Casement Window. The crank handle is in the way Read less