Give your cats the off-the-floor perch and security they love for bird/people watching or a cozy catnap. The Kitty Shelf has two metal brackets that slip between the windowsill and sash, with a vinyl tipped arm that braces it against the wall without marring. Supports up to 20 Lbs. Shelf is 12"x16", hardboard top is padded & has a removable/washable fleece cover.