The BLU-43 Dragontooth was a butterfly-style mine used in Vietnam. It's chemically activated, and has what's supposed to be a chemical deactivation system so that it doesn't remain a threat after conflict has ended. However, it doesn't always work. The BLU-43 is an interesting construction for a land mine, in that (assuming similarity to its Soviet clone, the PFM-1) it's basically a plastic bag filled with liquid explosive. When pressure is put on the liquid, it pushes a plunger into a detonator, causing an explosion. The explosion is usually not big enough to kill the target, but big enough to cause instant amputation of the target's foot.