We have a factory in Ningbo of China，brand new ,reasonable price and satisfactory after s,High levels of manufacturing technology and good quality! stainless steel oxygen sensor bung plug (O2 bung). Universal M18x1.5 thread pitch to fit virtually all O2 bung plugs. Used to seal off O2 bung hole when wide band O2 air fuel sensor is not in use. Easier access for installation and removal in tight spaces. Package includes: 2 rings and 2 plugs.