The 2” marking lights put out the same light under night vision devices as taped up 4” or 6″ chem lights and is designed to prevent accidental breaks and glow. The MARCO holds 30 – 2″ marking lights that give roughly the same lumen output as a taped up 4″ traditional chem sticks in a package smaller than a standard M4 STANAG mag. The MARCO is perfect for night time or low level light tactical training – drop them in a line to create a visible firing line and drop one under each target to approximate target location.