{"product_id":"faxon-firearms-arak-21-complete-upper-receiver-5-56-nato-16-piston-operated-urssb556","title":"Faxon Firearms ARAK-21 Complete Upper Receiver 5.56 NATO 16\" Piston Operated URSSB556","description":"Product Description\n\u003cp\u003eThe Faxon Firearms ARAK-21 Complete Upper Receiver is a gas piston actuated, fully assembled upper receiver system engineered to interface seamlessly with any standard AR-15 lower receiver. Installation requires no tools and takes under one minute, using only the takedown pin and pivot pin as interface points. Machined from aircraft-grade 6061-T6 aluminum billet in a one-piece design, this upper features a full-length Mil-STD-1913 Picatinny rail on top with laser-engraved optic placement markings, plus three additional Picatinny rails at the muzzle end creating a full M4-style quad rail configuration. The 16\" 5.56 NATO medium barrel is topped with the MuzzLok 3-Port Muzzle Brake for effective recoil management. The long-stroke variable gas piston system offers four settings, including three gas flow options for optimum cycling and one setting that blocks gas flow for single-shot operation. The ambidextrous, non-reciprocating, foldable, spring-returned charging handle can be relocated from left to right without tools. The included Barrel Assembly Unit (BAU) integrates the barrel, gas block, muzzle brake, gas piston, gas adjuster, and barrel trunnion into a single modular unit, simplifying maintenance and caliber conversion. The matte black finish delivers a durable, professional appearance suited for tactical and sporting use.\u003c\/p\u003e\n\n\u003ch2\u003eProduct Highlights\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrop-In AR-15 Compatibility:\u003c\/strong\u003e Interfaces with any standard AR-15 lower receiver via takedown and pivot pins only, with no tools required for installation in under one minute.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLong-Stroke Gas Piston System:\u003c\/strong\u003e Four-position adjustable gas block allows three optimized gas flow settings plus a single-shot no-gas-flow setting, enabling versatile and reliable operation.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAircraft-Grade 6061-T6 Aluminum Construction:\u003c\/strong\u003e One-piece billet upper receiver with full-length laser-engraved top Picatinny rail and M4-style quad rail handguard for maximum accessory mounting flexibility.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAmbidextrous Ambidextrous Ejection and Charging:\u003c\/strong\u003e Ambidextrous ejection port and a non-reciprocating, foldable, ambidextrous charging handle that relocates from left to right without tools for true ambidextrous operation.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eModular Barrel Assembly Unit (BAU):\u003c\/strong\u003e The BAU combines barrel, gas block, muzzle brake, gas piston, gas adjuster, and barrel trunnion into one removable module, making caliber conversions and field maintenance straightforward.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSpecs\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Faxon Firearms\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eModel:\u003c\/strong\u003e ARAK-21 Complete Upper Receiver\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMPN:\u003c\/strong\u003e URSSB556\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 816341021952\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCaliber:\u003c\/strong\u003e 5.56 NATO\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBarrel Length:\u003c\/strong\u003e 16\"\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBarrel Profile:\u003c\/strong\u003e Medium\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAction:\u003c\/strong\u003e Gas Piston, Long-Stroke Variable Setting\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReceiver Material:\u003c\/strong\u003e Aircraft-Grade 6061-T6 Aluminum Billet, One-Piece Design\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFinish:\u003c\/strong\u003e Matte Black\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Standard AR-15 Lower Receivers\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRail System:\u003c\/strong\u003e Full-Length Mil-STD-1913 Picatinny Top Rail; Three Additional Muzzle-End Picatinny Rails (Quad Rail)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMuzzle Device:\u003c\/strong\u003e MuzzLok 3-Port Muzzle Brake\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCharging Handle:\u003c\/strong\u003e Standard Ambidextrous, Non-Reciprocating, Foldable, Spring-Returned\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBolt Design:\u003c\/strong\u003e Model 39, Eight-Lug with Involute Profile\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eIncludes:\u003c\/strong\u003e ARAK-21 Upper with Ambidextrous Ejection, 16\" 5.56 Medium Barrel, MuzzLok 3-Port Muzzle Brake, Bolt Carrier Assembly, Standard Charging Handle, Lower Forearm with Screws, Three Aluminum Full-Length Picatinny Rails, Three Insulating Shims, Lower Recoil Lug with Spring Guide Rod, Dual Recoil Spring System, Shipping Box, Owner's Manual, BAU Removal Tools (Two Allen Wrenches)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cem\u003eDisclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product's manufacturer.\u003c\/em\u003e\u003c\/p\u003e\n]]\u0026gt;","brand":"Faxon Firearms","offers":[{"title":"Default Title","offer_id":44199779369082,"sku":"FLX-FXURSSB556","price":1003.98,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1679\/0365\/files\/308987508.jpg?v=1788377784","url":"https:\/\/tlooutdoors.com\/products\/faxon-firearms-arak-21-complete-upper-receiver-5-56-nato-16-piston-operated-urssb556","provider":"TLO Outdoors","version":"1.0","type":"link"}