Very easy to install. Holds the mattress in place with only two on the longer sides and one of the top and bottom. I was worried about my toddler hurting himself on accident crawling in and out of bed, but they press into the mattress enough that it isn’t a problem!All I can say is pay attention to the instructions I almost return these because I put them on backwards and they kept coming off. Once we got them on right they work greatGreat little product. However these brackets attach to a metal bed support bar. I use them on a hospital bed and the supports are U shape; the screws are too short to grab the other side securely. They rattle and slide a bit as a result. An option of just 1/4" longer screws would solve that!These were easy to use on any size bed frame due to being easily adjustableMy bed frame was too thin for this product. Seems like it would have worked great otherwise.This works exactly as you need it to. No slipping off at allI have a metal bed frame and at the foot of the bed I had to stuff cardboard so that the screws would reach. If you have a bed frame on the thinner side, don't get these, they probably won't fit.They do the job kinda..but my kid pushed the bed and the piece bent..but it does mostly work just not stable lol