I'll do my best to describe the design of the restraint system. I've included photos to hopefully help you understand me. Since I've used this restraint system both on a day-bed (twin sized mattress) and a queen-sized, I want to include that information as well. You see, I've read that this system only works on queen/king sized mattresses, but that's not true. If this worked on my day-bed, it'll work on about any mattress. So I'm confident enough to say you can use this on a small or large bed. It's going to be more comfortable on a large bed and it's going to go on a little differently, but I'll explain.
This is basically a total of 4 cuffs (2 ankles and 2 wrists) and a whole lot of nylon strapping, which is kind of overwhelming when you first see it. Once you've looked closer, there's little else to think about. It's not time consuming or confusing. The hardest part about "installation" for me is lifting the blasted mattress.
How to install the restraint system
No matter what size bed you're putting this on, it'll go on under the mattress. Simply lift the mattress, or if you're me, simply get your partner to lift the mattress while you place the restraint system underneath.
Locate the two ankle restraints once your mattress is lifted. Worry about getting the ankle cuffs (or you can do the wrist cuffs first, it doesn't matter) in place and the rest will be easy to put on. For the ankle cuffs, pile the straps on the center of the bed and let the ankle (or wrist) cuffs dangle off at the corners. Do the same for the all cuffs and you've basically got all your straps in place.
Now you need to make sure the long strap that runs down the middle and the straps that attach the cuffs to this middle one are straight and not twisted. This way your cuffs will go on without twisting of the straps. Think putting on your bra. You just don't want your straps twisted.
On a king or queen-sized bed, the complete system will look like an "I" under your mattress. If it looks like this, you've done things correctly.
There is a metal D-ring on the middle strap, which connects the cuff straps and the 2 vertical straps to the middle "connector strap." This connector strap is 60" long and obviously, is the part that runs the length of the mattress, in the middle.
Put your mattress back on. But say you have on of those thick mattress toppers. You could place the restraint system under it rather than having to pick up your mattress. Things will be more secure if they're under the mattress though, but if for some reason you cannot lift your mattress you can go this route.
Once the mattress is on, the restrainee should lie on the bed while the restrainer adjusts the cuff straps to properly restrain the person. Different sizes will vary. For instance, I'm 5 2" and when I'm the one being restrained, we need to adjust the cuff lengths shorter than when my partner is being restrained.
The good thing about this is once it's under the mattress, you won't need to lift it again to adjust. You'll simply use the adjusters located on each cuff to personalize your fit.
Installing on a small bed such as a day-bed
There's little difference between installing this system on a huge bed and a small bed. The only difference is the way you'll place the straps under the mattress. Instead of the straps all creating an "I" shape, on a small bed like a day-bed, the straps will be in the shape of two Y's. Looking at my photos, you'll notice this. It will be a Y near the bottom of the bed -- instead of the straight line you'll get with a big bed -- and another Y at the very top. Simple! This is because the straps are made long enough for a large bed, so when you put them on a much smaller one, the cuff straps won't be placed so far apart to create the "I," but instead create two Y's. Am I losing you yet?
No matter what size bed you're putting the system on, it will work the same way. You'll have the 4 cuffs hanging from under the mattress.
You may have excess strap hanging if you're using this on a smaller bed, but those can be tucked inside the mattress.
Strap measurements
All straps are made of a sturdy nylon, which will hold up to years of use, and a lot of wear. The nylon straps all measure just less than 1" wide. The cuff straps measure 59 1/2" from the D-ring in middle that attaches all straps together to the very end of the cuff strap. Keep in mind it's not the strap itself that is adjustable, but the cuffs. So the strap length never changes, but you're able to move the cuffs to the exact length needed, which is handy. The cuffs can slide all the way to the end of the straps or all the way to the middle and everywhere in between. Of course you'll never need to slide them all the way to the middle because that would put them under your mattress with the D-ring. But this does mean you have plenty of length to adjust to whatever size needed. I can't imagine these not being long or short enough for any person. The same measurements go for both wrist and ankle cuffs since they work the same way.
The cuffs
The wrist cuffs are only half as long as the ankles, since most of our ankles are bigger around than our wrists. My ankles measure almost 8" around and the ankle cuffs measure a total of 15" long. These fit both me and my partner with extra room, and are made exactly like the wrist cuffs besides the length. Everything else, besides length are designed exactly the same for all the cuffs. They all attach with keychain and swivel clasps and nylon straps.
The cuffs are just like the cuffs that come on the Door Jam Cuffs. They're 2" wide. They're lined faux fur (both inside and out) that feels velvety. These cuffs velcro. The soft velcroing strip measures almost 5 1/2" long and the rough velcro almost 4" long. The entire ankle cuff measures 15" long, laid open and not velcroed of course. This will fit tiny to large wrists and ankles. The wrists measure 10" long.
I think my wrists and ankles are pretty small, but I could be wrong. My wrists measure 5 1/2" around, and my ankles measure almost 8" around. The restraints fit both me and my partner while still having room.
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