The rough opening is almost certainy framed in 2x4. If you wall is 4.5" thick, for example. The safest option is to screw a 2.5" or 3" eye screw through the trim and deep into the rough frame underneath. Hang from the screw yourself to test it, then attach the jolly jumper with a carabiner to the loop below the clamp. My parents used a hook, not an eye screw and occaaional i could jump the spring off the hook. My kids had the over the trim clamp version until we moved to a house with no trim. It is the best baby product ever. I hope your kid enjoys it.