Sunlite 25136-su 42a/hal/cl 42w a type halogen bulb, medium base, clear sunlite halogen a type bulbs can last up to 1.3 years with normal household use of 3 hours a day and display a brighter, whiter light than incandescent bulbs. This 42 watt, medium based, a type bulb offers a light output of 750 lumens, a clear glass finish and has an average rated life of 1,500 hours. Great for portable lamps, ceiling fixtures, track lighting, showcase displays and most common residential and commercial lighting needs. Halogen bulbs produce more lumens per watt (lpw) and have a longer lamp life than standard incandescent lamps. You can lower operation costs by more than 30% by using fewer halogen lamps to produce a greater amount of light.