Jinming M4A1 Gen 9 Gel Blaster Barrel Interface to suit 16mm Aluminium Tube

Was looking for an inexpensive alternative to the metal outer barrels available on line for the Jinming Gen 9, something that can be made to a custom length to suit inner barrel and accessories.

This suits 16mm OD aluminium tube (16mm x 1mm - avail at Bunnings if you are in AUS) and a 9.5mm inner barrel - very tight fit and you will need to sand the aluminium tube. Made especially tight so the connection doesn't require glue and remains robust. If you are intending this for a floating handgua