All units feature a four year shelf life; independent laboratory testing; an ultraviolet dye for suspect identification; a superior, non-flammable and non-ozone depleting formulation; a soluble formulation which does not require shaking before use; approximately 75% more content per canister than the competition; safety locking tops with easy operation to prevent accidental discharge; special canisters to prevent leakage and chemical reactions from occurring; and a state of the art propellant allowing the last shot to shoot as far and as forceful as the first.