This Bren with its 11" barrel has proven a popular SBR candidate for customers wanting to convert it to an NFA firearm. Those who don't wish to register with the ATF can always equip it with our adapter kit that allows easy installation of aftermarket arm braces or other devices meant to help stabilize large format pistols like this. Chambered in .223/5.5645 and using the ubiquitous STANAG magazine from the AR15/M16, it easily accepts optics and lights on its top and bottom Picatinny rails. An effective two-port muzzle brake helps keep the pistol solidly on target and reduces recoil and muzzle flip. The CZ 805 Bren S1 Pistol is legally classified by the ATF as a pistol, and is intended by CZ-USA to be used as a pistol. Under current federal law and ATF policy attaching a stock to this pistol -- or attaching a device which is then used as a stock or intended to be used as a stock -- constitutes the making of a short-barreled rifle which requires registration with ATF and the payment of the applicable tax. Users of the CZ 805 Bren S1 Pistol bear the sole responsibility for ensuring their use of the firearm complies with all local, state, and federal firearms laws.