SPECS: 7.3 x 1.7 x 1.7 mm Weight: 178 grams DESIGN & DETAILS: Uses a 40-micron pre-filter Created with improved water resistance and battery life An 8,000 treatment lamp delivers a lifetime of purification Treatment size is 1/2 or 1 liter Treatment time 48 or 90 seconds The 40x40 micron screen pre-filter fits perfectly on wide-mouth one liter water bottles and removes particulates that can get in the way of UV light in water Comes with 1 pouch and 1 prefilter TECH SPECS: Requires 4 AA batteries