The DefTech 1315 was developed from the Smith & Wesson 276 Gas Gun (which is itself based on one of Smith & Wesson's revolvers, with the barrel and cylinder removed and replaced with a large-bore barrel, and a stock affixed to the pistol grip). In fact, the DefTech is essentially the exact same weapon, but fitted with a modern synthetic thumbhole stock, synthetic foregrip and improved iron sights.