Diamondback Firearms 5.56mm NATO/300 AAC Blackout 7in Black Nitride Modern Sporting Pistol – 30+1 Rounds – Diamondback Firearms creates practical firearms that are built to last. The Diamondback Firearms DB-15 semi-automatic pistol is an excellent choice for home defense, hunting and competition. Each and every firearm is built from the ground up right here in the USA. But what is better than having one high quality AR-15? Having one-and-a-half high quality AR-15s! This 5.56 NATO semi-automatic pistol also comes with a separate complete upper assembly that’s chambered in the increasingly popular .300 Blackout caliber. You’ll be able to quickly switch from one caliber to the other with ease by simply pushing out a couple of pins and popping the other upper onto the lower. Both upper assemblies feature chrome moly barrels with black nitride finishes and M-LOK handguards which are ready for the addition of any accessories you choose to add. The lower receiver comes complete with a pistol buffer tube and a Magpul pistol grip, a favorite option among a large percentage of AR-15 owners. Take the quality of Diamondback Firearms, combine it with the versatility of an additional complete upper chambered in another popular caliber, and you’ve got a winning package that you’re sure to enjoy for years to come!