LED Retrofit replacement bulbs for C7 and C9 Christmas lights can save plenty of money in energy costs. Traditional incandescent C7 or C9 bulbs use between 5 and 7 watts of power per bulb. LED retrofit C7 and C9 LED replacement bulbs use less than a watt and can burn for more than 50,000 hours. That's pretty much a lifetime if you use them just for holidays. So don't through out those old fashioned light strings from years ago. Just replace the old C7 and C9 Christmas lights with long-last and energy-efficiten LED bulbs and save. And we carry other styles too.