An elderly relative has been falling out of bed, so I looked for rails. There are versions that fold down along the bed axis - which won't work because the user's wheelchair is there. There are telescoping options - that give a max of 10" of additional protection (pretty useless) AND which use those spring loaded balls which are often SO hard to use. NOT going to work for someone sleepy in the middle of the night. I was so pleased to find these. They fold parallel to the bed axis so won't interfere with the wheelchair. Their folded height is much lower than the mattress height, so won't get in the way of getting in and out of bed, and that big trigger handle is SOOO much easier for them to use. I am very pleased. They just came today and they seem like they are quite sturdy. I have boards ready to extend the included brackets so they reach even further under the mattress. The brackets have holes pre-drillled, so if your use case has something to drill into, those wouldn't be needed.
Update: the brackets are a little thin for a heavy individual - truly rolling onto them could result in them bending instead of blocking. But the bottom frame is 1" square steel tube that comes predrilled with extra bolt holes on both ends. Should the brackets be problematic, I plan to simply bolt sturdy boards directly to the frame. To the manufacturer...even small triangle at the main bend points instead of mere bends would go a long way to increased stability! (makes me wish I could weld)

My Mom was rolling out of bed. I bought these rails for her and just installed them a few days ago. My Dad and I installed it together with nothing other than our drill. We had it together in less than five minutes. What I was worried about was how it would look. The reason being is my Mom is only 66 years old and I did not want to put these on her bed, like she was some old person. I want her room not to look like a hospital room or nursing home room. However, after installing them, they don't look like that at all. They actually look great. They not only will keep her off the floor, she can use them to either get up in the bed or sit down in the bed. If she doesn't want to use them, she can just click the red button and put them down. They also are easy to slide over in and out of bed. These things are visually pleasing to look at, very functionable, easy to install, and a great price as well.

Excellent
Check for offset. 3 or5"

During the time that I was in the hospital and subsequent rehabilitation, I found these handrails on Amazon. I was going to put them on the twin bed in my guestroom, where I would sleep until I got my strength back. The bed is an adjustable bed. One of my brothers measured all of the segments of the bed and created a hinged plywood platform base for the handrails. It has worked like a charm. The only adjustment he had to make was to reverse the mounting brackets to allow for the mattress thickness. We ended up not needing the additional 5 inch brackets, even though he had ordered them just in case. I would highly recommend these. They fold away out of sight when they are no longer needed, alongside the sides of the mattress.

L brackets are very heavy duty and do not bend when side pressure is applied to the rail. Surprisingly high quality; don't see this level of quality very often.
Release is very easy for an elderly person to use. Cons: None Pros: Everything about the rail.