This is just plain cool. Push the activation button, stick the wand in a glass of ‘questionable’ water and watch the wand glow. Swirl the wand and wait for the light to turn off while repeating the following words, “A La Peanut Butter Sandwiches…A La Peanut Butter Sandwiches…”(…these words must be spoken or the unit will not function properly…) Presto! Safe drinking water anywhere on the planet. No tablets, no drops, no iodine or chlorine aftertaste. Works by ultraviolet light to kill 99.9% of all harmful organisms. If the water is especially murky, we suggest filtering it first – unless you like drinking brown water with unidentifiable floaties. Purifies up to 32 ounces (1 liter) in 90 seconds or less. Works for up to 8,000 treatments. The optical sterilizing sensor also doubles as a flashlight for that night-time walk to refill your water bottle. Neat. Protective pouch included. 6”x1.5”x1”, 3.6 oz. (with two 123A batteries).