These are Glock OEM thread protectors. They are available in 1/2x28 RH threads or 13.5x1 LH threads.
RH thread protectors fit Glock Gen 4/5 17/19/34 right hand threaded barrels.
LH thread protectors fit Glock Gen4 17/19 left hand threaded barrels.
Please Note: Packaging nomenclature may vary on RH thread protectors.
