Lwrc six8-a5 6.8 spc 16" bbl 30rd black FEATURES-Black-16" cold hammer forged, spiral flutedbarrel-1:10 twist rate-5/8 x 24 muzzle threads-Adjustable compact stock-MagpulA(R) MOE+A(R) Grip-Adjustable 2-position gas block-Proprietary upper & lower receivers optimized for the 6.8 SPC IIcartridge-Fully ambidextrous lower receiver-12" user configurable rail system-LWRCI enhanced fire control group-Skirmish(TM) back up iron sights-Birdcage (A2) flash hider-Ambidextrous charging handle-Ambidextrous sling mount-Comes with Picatinny rail sections for attachments-30 round magazine capacity Other Features: Piston operated, spiral twist, aluminum upper/lower receiver, 12" modular rail, skirmish sights, ambi controls/charging handle uses unique magpul 30rd magazines-standard 6.8 ar-15 magazines will not work.Specialized upper and lower not interchangable with ar15