Re: [skydonkey] Low Crane Jump
B12's aren't standard, but I've seen them on plenty of harnesses. They're very convenient for gearing up in tight spaces. I can't recall how much they cost as an option, but they're definitely available.
On B12's, be sure that you snap the B12 before taking the PC out to go hand held. I've seen people snap the bridle into the leg strap on accident. Also, check the B12's just before exit, I know a B12 somehow (no idea how) came loose during the climb over of the rail on the bridge here, leaving the jumper outside the rail and minus one leg strap.