9mm M13.5×1 Left Hand barrel Thread protector. It is machined from US made steel to very high quality standards on CNC lathes. It has a durable black oxide finish. It is designed for European metric threaded barrels.
Made in USA!
It has 15MM wrench flats to tighten securely.
Length is .525″
Outside diameter is .640″.
Please confirm your thread size before ordering.