"Whether out in the wild or simply getting water from an unfamiliar source, play it safe with your drinking water by using the Steripen Classic 3 Handheld Water Purifier. The workhorse of the Steripen family, the Classic 3 uses ultraviolet light to make your drinking water safer, wherever you are. Steripen's germicidal ultraviolet light destroys over 99.9% of waterborne viruses, bacteria and protozoa (giardia) in water. Its 8,000-dose UV lamp purifies .5L (16 oz.) of water in 48 seconds or 1L (32 oz.) in 90 seconds. This handy purifier runs on 4 AA alkaline, lithium or rechargeable batteries (not included). Suitable for hikes, travel, or any situation when pure, drinkable water is not available, this water treatment device uses no harsh chemicals, and won't change the taste or color of the water, or add an unpleasant smell. Simply press the on button, place the lamp in your water bottle and stir. The lamp automatically shuts off when the treatment is finished. Mfrs. 3-year limited warranty. 7.3""L x 1.7""W x 1.7""D. Weight with Batteries: 5 oz.Manufacturer model #: SP-MP-EF. Compact and effective personal water purifier set Uses UV light to purify drinking water UV lamp destroys over 99.9% of waterborne viruses, bacteria and protozoa (giardia) in water Purifies .5L of water in 48 seconds, or 1.0 L in 90 seconds Easy to operate with single-button control"