The good news...these STICK on on even rough surfaces!! im decorating a friends wedding in a couple weeks & the venue is VERY strict on basically not using ANYTHING that will leave ANY kind of mark. i made a fake shell light to hang above the table the marriage license will be. its a old clock frame that was maybe thin MDF, the shells are wax paper with thin metal connector loops, and the lights are 2 battery powered led strips so its pretty light weight.my first test above my sink i used a command hook..BIG FAIL! 3 hours later it fell & the frame broke luckily it was fixable but has a "scar" lol then i got these, for this test i hung it over my bed and didnt attach the shells (in hopes that if it falls it wouldnt break) i figured i would leave the "shells" in the box i put them in and sit it on top of the light (as my pic shows) so i knew for sure it would hold the entire weight once its fully assembled. as you can see my ceiling had a crappy texture thing, the venue has stained wood planks ( like a floor) once placed this hook with my light frame & box on top wasnt going anywhere! after 2 weeks ( life got in the way it stayed longer then i intended) i applied heat like the description says, first i tried a microwave heat thing but after 3 min of holding it up it clearly wasnt going to work. then i got a extension cord & hair dryer, on high heat for 8-10 min...it WAS working but then i got impatient, my fingers were getting sore trying to lightly pull the hot plastic and i pulled too hard...yeah not good lol it took off the paint/texture as you can see in my pic. so to sum up...they REALLY WORK WELL, but make sure you have the patients to remove with heat!UPDATE: thankfully the venue already had a hook above the table for the light i was going to use these hooks on because i ended up needing 2 of them to help (there were already 2 "real" hooks there) hold the rod for macramé curtain in the background of the one picture. i also used 2 on each window in the other picture to hold up some makeshift "rods" for the window sheers & florals. the rods were actually rods from back ground stands, they have holes to attach to the stands & these hooks went right in the holes & held it up for 3 days! all the surfaces i put them on were "stained" wood & they peeled off clean (no residue) & damage free without the need for heat to remove them...i would def use again, they were a life saver for being able to decorate the wedding! the venue owner was so impressed with these & the "scotch" sticky plastic velcro kind of things i used she asked me to send her the links so she could tell future clients (: