Mini Lights are a wonderful way to show off your larger display pieces in your home. Some may know them as "Christmas Tree" lights; however, these light strands are Commercial Grade with wonderful features. Unlike light strands that most are used to these Commercial Grade 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 Commercial Grade light strands is a UL listing for indoor and outdoor use, the strings average 3,000 hours of trouble-free lighting.