Radical Firearms Complete Upper Assembly, 7.62X39, 16 Barrel, 1:10 Twist, Black, MLOK Handguard, A2 Flash Hider RF00397 The Radical Firearms 7.62X39 upper is perfect for the novice or advanced shooter wanting to finish out that build and hit the range. No matter what your style of shooting is" Radical Firearms has you covered.