Radio tower incandescent light bulbs are used in high tower applications like TV, radio, cell phone towers and microwave towers. It's one of those difficult to reach areas that are typically taken on by experienced tower technicians in the field. These ensure that your tower is going to be seen by airplanes and helicopters. They are 620 watts, and the prefocus mogul base make It a standard for companies who change these incandescent light bulbs for a living. They are made from a heavy-duty construction especially the filament which can take a lot of vibration. The base is exclusive to this application making the bulb always the right fit for this specialized application. By federal law in the United States, you must maintain lighting in communication and TV towers without fail. That means whenever a light goes out someone has to climb the tower to change the light bulb or do other maintenance. It's no entry level job, and yes, you cant be afraid of heights so choosing the right performing light bulb becomes extremely important. The fewer times you have to climb a communication tower, most people would say that's better. That's why we carry lamps that are going to last a long time, and they have a good track record with many of our customers already who are tower climbers or tower techs.