My disclaimer: " These are free items (Gifts) but I will entertain a return gift if the other party (that'd be YOU) feels obligated by regional social norms or generous or whatever. If more that one person would desire the item I will entertain making a choice as to the new owner based on some criteria as yet undetermined. I reserve the right to withdraw an item for any reason (bickering would be one reason). I will present the item as best I understand it, I will list faults that I know (and recall). If the item is dangerous (could put an eye out or something without special instructions) I may limit its demise to someone I know and trust. I assume the new user will use the item as designed and intended and for lawful purposes. If the new user in injured with the item I will believe it is due to negligence, willful ignorance or stupidity (or any combination of two or in extreme cases all three)." Hi-Res http://longrangehunter.com/trade-free/bota-bottle-filter.jpg I used a few of these in Canada on a bear hunt. I filtered raw water (not boiled) from a heavily beaver infested stream and suffered no ill effects. Mine fit well and tight into a Nalgene bottle.