I am not sure what value the community would place on Frag Mines. But the wiki says "player to player value is about 15,000 - 20,000 caps" for motion sensors.
I have something like 30 to 40 maybe more Motion Sensors. I don't use them. But I would like to get my hands on some Frag Mines. I am not going spam locations with them to cause trouble. I just want them for my own use.
So lets say one motion sensor = six Frag Mines? I am willing to barter. PM if you are interested.