Snakebite kits are small suction devices that are used to pull poison out of a snake bite. These little vacuum pumps are a convenient and effective way to do nipple pumping and other types of vacuum pumping. With long term use the results can be permanent or at least semi-permanent.
Snakebite kits are available from camping, first aid, and survival stores. There are a lot of different types (for example, syringe based ones), but for the purposes of pumping the suction cups are generally easiest and cheapest.
Usage and Pictures
Use (in a body modification context) is as simple as applying the suction device over the nipple (or clitoris or whatever is being pumped). While temporary enlargement is simple to obtain, over time, permanent enlargement may be observed.