From aly: There's No Escaping These!,

These heavy duty cuffs from Fetish Fantasy are made from neoprene and nylon. They are very comfortable to wear for both short periods and extended periods of time. They have double Velcro closures which is largely what makes them so heavy duty. There's no way you'll pull free from these cuffs. This set up makes them great for attaching to each other, but not so great for attaching to other restraint sets. I really liked the cuffs themselves - they're great cuffs and very comfortable. This set also comes with a cheap little blindfold, which does work, but is very small and thin.