Introduced 2009. Similar to AR-derived M&P15, with gas piston. Chambered in 5.56 NATO. Features adjustable gas port, optional Troy quad mount handguard, chromed bore/gas key/bolt carrier/chamber, 6-position telescoping or MagPul MOE stock, flattop or folding MBUS sights, aluminum receiver, alloy upper and lower, black anodized finish, 30-round magazine,16" barrel with birdcage. No. 812006 has standard handguard); PSX had Troy quad mount handguard.