Aero-Tech is the only manufacturer of 20,000 hour rated, long-life incandescent bulbs in America. The less time and money spent on lights bulbs the better. Aero-Tech Light Bulbs are the brightest idea in lights bulbs since the days of Thomas Edison. Not one break-through, but THREE: 1) Extra durable filament, 2) Extra protection against vibration, 3) Extra strength to absorb voltage surges. 26 times the life of average bulbs saving labor & replacement costs. Brass base eliminates corrosion and prevents base from sticking in socket. 5 support wires help provide long life with excellent resistance to vibration and shock. Special rare Krypton gas mixture reduces heat and prolongs filament life. 150-watt A-21 20,000 hour long life incandescendant frosted light bulb, (6-pack).