A tactical weapon.
The smokescreen makes it harder for your enemies to shoot you. It is especially effective against laser weapons, which are unable to shoot through smokescreens at all.
The smokescreen causes no damage to enemies, but will block lines of sight and disrupt laser fire quite nicely.
The Heavy Smokescreen lasts a bit longer then this smaller version.
Be aware of any wind as the smoke will move with the wind, and may negate any help you thought you had if it blows away.