Maintenance Engineering Ltd. Incandescent Lamps have been designed with Premium Quality construction. The Multi-Watts special Nitrogen Argon gas fill works to retard blackening and increases filament life. The solid single coil of pure Tungsten extends the lamps life and saves 12% in energy costs alone. Five filament supports are used to resist shock and vibration, which also extends lamp life. Maintenance Engineering uses brass bases, due to their ability to resist corrosion and freezing in the sockets.