It's 1/16" fiberglass cord from McMaster Carr. I use the bail to lift the pot out of the windscreen, and then hold it by the fiberglass insulation to pour w/o burning my fingers. I'm not a fan of the silicon rings. I've got fat fingers and they are too narrow. Plus this serves double duty as a spare 10' length of cordage for emergencies.
Instructions to wrap the can like that were once posted on Minibull Designs website. I first saw it several years ago. I don't know if it's still on there or not. It
s the same stuff he uses as a priming wick for his pressurized alky stoves. (disclaimer- not trying to plug tinny. I'm not a fan, but I feel it's right to give credit where credit is due)
(edit: tinny does sell the stuff at $0.20/ft. I'd compare that to McMaster, but McMaster doesn't tell you the shipping until after your order is shipped. I just checked, it's $0.34/ft for orders up to 50', part no, 8818K41)
(edit2: Ziff- I'd still encourage you to post yours. It's fun comparing notes and seeing what solutions others have come up with. I don't have any original ideas in my stove setup. Just bits and pieces of other kits I've seen on the web that I liked, put together into one kit that I'm pretty happy with)