Mini Lights are a wonderful way to show off your larger display pieces in your home. Some may know them as "Christmas Tree" lights. These light strands remain lit even if one light bulb were to burn out. Simply replace the burned out light bulb with the replacement bulbs given and continue enjoying the beautiful ambiance. We have personally tested these strands and replacing bulbs is a simple and easy process. The second feature that we love about these light strands is a UL listing for indoor and outdoor use, the strings average 1,500 hours of trouble-free lighting.