Oper8 5" metal outer barrel extension CCW The Oper8 metal barrel extensions are made in the UK from aluminium and are designed to extend the length of your outer barrel, they range from 1" to 7" to give you the best variety of sizes to cater for what you need. Features: - Screws straight onto any -14mm thread - Made in the UK - Aluminium construction - CCW thread which fits onto most brands - 22mm diameter - Seven sizes available Each barrel extension has a male and female thread to go straight onto an outer barrel and has a similar width to the standard M4 and AR type outer barrels. Pick from lengths in inches between 1" and 7" to suit your rifle as best as possible. Each barrel extension has a barrel support space running through it, suitable to support most brands of inner barrels. The inner diameter is approximately 10mm. This barrel extension is made in the UK from strong aluminium and screws tightly onto your original outer barrel to prevent any wobble or damage caused by the weight of a suppressor. Either extend your outer barrel a small amount to get your suppressor just crawling out of the rail system or a length to compensate for a new, longer rail system and even to help with extending your rifle to a suitable 'DMR' length barrel.