Halogen bulbs are incandescent bulbs. This surprises many people who assume halogen bulbs are not at all the same. Halogen bulbs, however, are filled with a special gas that actually rebuilds the filament and provides longer average lifespan than normal incandescent bulbs. They come in different shapes and sizes for various different uses. The PAR series of halogen bulbs are flood shaped with heavy, thick glass that is common to many medium to large sized halogen bulbs. PAR stands for parabolic aluminized reflector. These types of bulbs will provide you with a higher light output, a more white-colored light (a higher color temperature - approximately 3000K), and longer life than normal R or BR reflectors.
The PAR30 bulbs are the most commonly purchased and used PAR lamps available. You can tell what kind of PAR lamp you have by measuring the distance across the widest point of the bulb. The number after 'PAR' represents the number of eighths of an inch the bulb diameter is. Therefore, PAR30 lamps are 3 3/4 inches across.
PAR30 lamps are widely available from Sylvania, GE, Philips, Westinghouse, and most other small bulb manufacturers. They have standard bases and are able to be used indoors or outdoors. They can be directly exposed to rain or snow and still function normally. They do not need to be covered by a light fixture, which makes the PAR30 lamps handy to use.
The Sylvania brand for all PAR lamps is Capsylite. Philips brand for all PAR lamps is Halogena. The GE brand for all PAR lamps is Edison. The Westinghouse line uses only PAR to describe these bulbs. You can get the bulb in NSP (narrow spot), NFL (narrow flood), FL (flood) and WFL (wide flood) beam spreads. The NSP is about 9 degrees, the NFL is about 25 degrees, the FL is about 40 and the WFL is about 50 degrees. If you want to light up a large area, then use the FL or WFL. If you want to focus the light into a small area, try the NSP. You can get all of these options in 120 or 130 volt. The 120 volt bulbs will be a slight bit whiter and brighter. The 130 volt bulbs will last about twice as long as the 120 volt bulbs. You can get thes bulbs in 35, 50, 60, and 75 watt versions. Some models are also available in long neck type. These bulbs are handy for can lighting and other fixtures that have a deep shape, with the base far inside of the fixture.
People use Sylvania PAR30 lamps a lot in track lighting; they are the most common track lighting used today. Many stores and restaurants use this bulb for the majority of their general lighting needs. The items shown under this light will appear more brilliant and will display a brilliant color.