If you see photos and movies of GI's then you will have noticed some kind of pack on the helmits.  That's your wound/sulphar packs and I didn't have one up there.  What you see is a pair of tracers in 7.62x51mm NATO.  At the time I had a borrowed M-14 and my intent was to use the tracers to mark a target.  Since a lot of times you couldn't figure out where you were being shot at from we had a thing worked out where if you spotted the source you loaded a tracer into your rifle and yelled out "Mark it!".  You put the round right where you wanted everyone else to fire.

These rounds were hard to get and the only real source was from the dude who had the PIG.  That's why they are still in links.  When I gave them back he just clipped um back on the belt.