These barrel extensions are made from steel and have an inner diameter over .400" to work with any pistol that has either 14-1 LH or 1/2"-28 right hand female threads.  Permanently attach to your pistol or SBR to bring the barrel length to 16".  Our extensions have a 5/8"-24 male thread on the end to be able to install a flash hider or use one of our fake suppressor sleeves to cover the barrel extension.

There is a spot drilled location on the rear for drilling across the extension for installing a blind pin then welding over the pin to satisfy the ATF's requirements for permanent barrel attachments.  These can also be silver soldered or welded half of the circumference to be considered a permanent attachment.

When choosing your size measure the length of your barrel, then measure threads that are sticking out from the front sight or stopping point of your barrel, subtract that number and then choose the extension that once installed it will be over 16".  So a 10" barrel with .625" of threads will need a 7" extension to be over 16" when installed.