Travel well with the SteriPEN Traveler Water Purification System. SteriPEN eliminates 99.9% of bacteria, viruses and protozoa that cause Traveler's Diarrhea. Disinfect fresh (non-salt) water or bottled water in any country. Features tapered neck and 16 oz. or 32 oz. volume selection. The SteriPEN Traveler is designed to fit perfectly into commercial water bottles, a key benefit when traveling to at-risk countries where even the bottled water quality is unknown. UV lamp provides 3,000 treatments. WQA approved. Powered by 4 AA batteries (not included).