Rite Farm Products Infrared CLEAR or RED heat lamp light bulb. Available in 125- and 250-watt options. The clear bulb works great for large chilly coops, and the red is great as an attractant for chick brooders.
Lasts 20 percent longer than standard heat lamp bulbs
uses standard 120-volt power
standard type A screw in power base (same as your household bulbs)
brass base to minimize corrosion and "freezing" in socket
average bulb life is 6000 hours.