
It's a padlock, with an electronic timer that can be set between 1 minute and 99 hours. Once started, the lock cannot be opened until the time us up.
They don't look strong or reliable enough for serious bondage, but look great for fastening yourself into a wetsuit. Wrap a small chain loosely around your neck, fasten one of these between the chain and the wetsuit zip, and that's it .... you're locked in until the timer runs out or you cut the suit off with scissors.
I've just ordered one - I'll let you know how I get on.
Meanwhile, what's the longest anyone has been fastened in a wetsuit? How did you manage with little things like overheating or going to the toilet?