R501 (5W5) Side and Tail Bulbs
The R501 (5W5) capless filament bulb is most commonly used for vehicle side and tail lights. Due to it's small size, the R501 is a highly versatile bulb that is used in various positions around vehicles, including but not limited to number plate, high level brake and interior map reading lamps.
Below are the most popular R501 bulbs from Ring, to see the full range click here.