Each hook is 25 inches tall and 15.25 inches deep, and the mounting kit suits wood, studded, block and brick walls. The foam stops a ladder rail or a chair frame from scratching.
You will work overhead or at the top of a stud wall, so set the ladder on a level floor, face it and keep a hand on it while you drive the screws. Fasten the brackets into solid framing (a joist, a rafter or a stud), never into drywall alone, and read the instructions in the box first.