SteriPen Classic: Using four AA lithium batteries, the Classic gives you the power to purify an incredible 200 half-liters of water with a single set of batteries, providing you with that extra confidence to know that you’ll have access to safe drinking water whenever you’re hiking or camping in the wild.
SteriPEN Classic’s tapered end provides a snug fit with water bottles, and with the SteriPEN Fits All Filter, works even with wide-mouth water bottles.
The Classic with Pre-Filter pack is all that is needed when camping, hiking, backpacking or traveling is all you need if you all ready own a wide-mouth 1 liter water bottle. Use the 40x40 micron screen Pre-Filter to remove particulates from the water. The Pre-Filter is designed to be stored directly on the wide mouth bottle
Big Book Catalog, Issue:67, Page:535