This BCA AR-15 complete 300 Blackout pistol length upper has a 10.5" heavy barrel with a parkerized finish, and features a 1:8 twist rate, with a pistol length gas system. It includes a 9.5" MLOK rail, an M4 flat-top billet upper receiver, a BCA bolt carrier group, a flash hider, and a rear charging handle. This 300 Blackout upper is compatible with any mil-spec AR-15 lower. Shop more .300 Blackout Uppers! Check out Magazines here! {{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="56"}} *Note - We strive to provide the most accurate photographs of our product. Variations may occur in the skeletonized section of the handguard/flash hider you receive {{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="42"}}