The HK P2A1 is a single-shot, break action flare pistol designed for signaling and illumination purposes. It can fire either 26.5 mm or 25 mm flares, or smoke cartridges. Adapters are available to use commercial 12 gauge flares available at sporting goods stores. The body of the weapon is mostly polymer composite, with the barrel and breech being made of steel. Very rugged and simply designed, the P2A1 has a life expectancy of about 1500 shots of full power flares. Past that point, barrel erosion makes the weapon unsafe.[citation needed]