Do you mean snake bites... or snake bite kits, the kind that extract venom?
If the former, I'd try to avoid it as a solution, whether or not it actually works, it's damned hard to train the snakes to bite you exactly where you want.
If you mean snake bite kits, I would suggest you look into a pair of Sawyer Extractors. They are visciously effective, producing substantial suction... and you can observe through the clear plastic extractor cups, whereas the rubber suction devices are opaque.
http://www.bdsmlibrary.com/forums/at...6&d=1194808472
http://www.bdsmlibrary.com/forums/at...7&d=1194808472