Water Bottle Pre-Filter is to be used with the SteriPEN Ultraviolet Water Purifier (SKU # 69478). When clear water is not available, use pre-filter until water is clear, then treat with SteriPEN. For use only with NalgeneA(R) 32 oz. wide-mouth bottles.Removes particulates and protects against water bottle recontamination.Easy storage on bottle, and creates a water-tight seal when used properly with the SteriPEN Water Purifier.Size: 2.7" diameter.Weight 1.5 oz.
