Combine traditional Christmas style with energy efficiency in your decorating. The retro-shaped C9 bulbs you love with the latest LED technology for the best of both worlds. Use them indoors or outdoors. However you choose to use them, these fun C9 lights are sure to add a vibrant pop of colour to any space! These bulbs feature continuous-on technology, which allows the light string to remain illuminated even if one bulb burns out or becomes loose.