We're not talking about the same thing, then, Jack. My wrist supports are some sort of elastic clothing material (could be Neoprene, I have no idea, but I don't think so) about 5mm thick. They have a loop for the thumb, so that it stays in place. Apart from that, it's a long piece of material with internal & external Velcro fastening so you can wrap it as tight as you like. The main body of it is about 6cm deep, so it covers only the wrist; if you google wrist support, half the stuff you'll find goes halfway up the forearm & talks about carpal tunnel syndrome...

Helping with that isn't the purpose of mine and, I suspect, ditto for pfr. But he can speak for himself, of course! Mine help support the wrist under any strain (and protect from knocks if you're daft enough to wind up in goal!), help keep it warm (which allegedly is better for healing) and, importantly, remind you every time you try to flex the wrist too far. Which, where guitar playing is concerned, is how we wind up with knickered wrists in the first place, let's face it! ;-)

Kanckered? Cankered? Knackered! *ahem* Knackered wrists was what I meant to type. But knickered wrists was much too good a typo to edit out! :D