The Super-Brite rope light, 5/8 Inch in diameter, is made with superbright bulbs (6V/100MA). Each bulb emits 66.7% higher brightness than the standard miniature bulb. Since we only use the highest-quality PVC material along with UV additives, the Super-Brite Flexilight can be used in indoor or outdoor applications and can withstand both freezing and scorching weather.