This is the device that uses patented light technology to reduce the healing time of cold sores. Its two LEDs generate safe 1072nm near-infrared light that is absorbed into the skin to strengthen the immune system and help make local cells more resistant to HSV-1 (the virus that causes cold sores). In clinical studies, the device was found to accelerate the healing of cold sores up to four days faster than using sloppy over the counter cold sore creams. Users only need three 3-minute treatments every four hours over two days to help speed healing. Requires one 9-volt battery. 4 1/2" L x 1 1/2" W x 1 1/4" D. (3 oz.)