Quad Rail w/Sig Kit Description
5.56 NATO or .300 AAC Blackout cal., pistol length gas system, 7 1/2 (5.56 NATO) or 10 1/2 (.300 AAC Blackout) in. chrome moly high-end barrel, A2 flash hider, laser etched M4 feed ramp flat-top T-marked upper receiver, forged lower receiver, AR-15 pistol buffer tube, free float quad rail with 7 (5.56 NATO) or 10 (.300 AAC Blackout) in. handguard w/o end cap, low profile gas block, full auto chrome-lined bolt carrier group Mil-Spec charging handle, pistol buffer kit, SB-15 SIG arm brace (5.56 NATO) or SIG arm brace only (.300 AAC Blackout), black Mag-Phos barrel finish, black anodized receiver. Disc. 2017.