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.

R bulbs have wide beam angles that create broad beams of light. Their length makes them good for use in large can fixtures.