Bosch 80031 Glow Plug Bosch patented Duraterm technology enables the glow plug to reach higher temperatures more quickly for fast engine start-up Nickel-plated rolled threads for increased strength and prevent seizure Twin Viton seals Promote longer life by protecting the coils against damage caused by exhaust gases If one glow plug fails, chances are the others won't be far behind. To minimize vehicle down-time and save on labor costs, Bosch recommends changing all glow plugs at the same time. Bosch is currently the OE glow plug on most European diesel vehicles. For Domestic & Japanese vehicle applications, Bosch Glow Plugs are designed to meet and/or exceed the OE glow plug specifications.