DieselRx DRX00138-8 - Glow Plugs For Ford 7.3L Powerstroke Engines - Pack of 8 Allows for faster engine startups, Helps reach optimum temperatures quickly Controls current draw for rapid heat of coil, resists corrosion and vibration Superior electrical insulation and high thermal conductivity, Protects coils from exhaust gas damage DieselRxglow plug peaks approximately 40F higher during the initial in rush of current. The lower stabilized temperature translates to a longer lasting glow plug. This purchase includes set of 8 DRX glow plugs