It’s a mine. 🙂
You place is just like any other mine /device and it get triggered when an enemy walks over it.
Sadly I never saw it work or what happens if it would have worked but it is suppose to have a very large area of effect vs enemy soldiers.
Something like an all around Claymore Mine.
Hope this explanation helped a bit.
*You set it, and this one is small and hard to step by VC. But you can do another thing, build a mine field, when VC go through it, you can throw a grenade to trigger all of them by chain of explosion. Then the effect will be awesome. XD
mines are most effective when you donjt erase your footprints i will intentionally leave a crap ton of footprints and right in front of one ill place the mine works 9/10 for me especially since i sometimes go on max heat missions its hilarious i once caused the game to lag for 4 minutes because a bouncer killed a VC QRF of about 50 guys (only 1 squad member survived this mission…)