Combine traditional Christmas style with energy-smart efficiency in your decorating. The Eco Smart 100-Light LED Multi-color Light Set combines the large, retro-shaped C9 bulbs you love with the latest LED technology for the best of both worlds. You get 66 ft. of bright, brilliant light at a fraction of the energy cost of incandescent lighting. Connect up to 24 sets for convenient, one-plug decorating. Use them indoors or outdoors. However you choose to use them, these fun C9 lights are sure to add a vibrant pop of color to any space! This light set features continuous-on technology, which allows the light string to remain illuminated even if one bulb burns out or becomes loose so you can keep your seasonal scene largely intact. The long-lasting, super-efficient LED bulbs use up to 80% less energy than traditional bulbs, keeping electricity costs minimized. And with weather-resistant sealed sockets, you can feel confident that your light display will stand strong throughout the holiday season.