PETN

PETN, or penthrite, which is more properly called pentaerythritol tetranitrate is probably the least stable of the modern military explosives, but it does have a long shelf life. It was first used after World War I and it is closely related to nitroglycerin. PETN is usually found in the form of clear crystals in a water solution. It is easily detonated and it is used in blasting caps and other types of initiators.