A red USCM issued flare. There are instructions on the side, it reads 'pull cord, make light'. But in this case, load it into the flare gun. This cannot be used in lit or dead flares. It can be used to light up enemies.
A green USCM issued signal flare. The telemetry computer works on chemical reaction that releases smoke and light and thus works only while the flare is burning. Used to signal for CAS.