These bulbs produce a narrower, more concentrated beam of light than floodlight bulbs. As LEDs, they last longer, are more efficient, and produce less heat than other types of bulbs. They also withstand vibration and are shatter resistant. Brightness is measured in lumens; the higher the lumens, the brighter the bulb. Bulbs with a warm light appearance have yellow tones. Bulbs with a cool light appearance have white/blue tones and are good for inspecting. A bulb’s estimated yearly energy cost is based on 3 hours of usage per day at $0.11 per kWh.

PAR bulbs have narrow beam angles that provide more focused beams of light than other spotlights. A short length allows them to fit in small can fixtures without protruding. Bulbs with a 5° beam angle are designed for dock lights. The narrow beam shoots light straight to the back of a docked truck. They won't wear out or fail from frequent movement or jostling.