Generally, the way to measure of effectiveness of a water filter is by the size of particles it can filter out. The personal water purifier by Survivor Filter filters down to 0.05 microns so you get a very fine micron filtering that removes extremely small particles and parasites like Giardia lamblia!
The Survivor Filter works similarly to the PRO-LE nanofiltration system but instead of a pumping action, you use your own mouth suction to draw clean water via the filter's mouthpiece. This personal water filter uses three stages of filtration.
The Survivor personal filter is attached to the thread of a bottle via the filter's removable screw on cap which acts as a bottle thread adapter. The screw on cap (inlet) features a cotton pre-filter pad that acts as the first stage of filtration.
The second stage of filtration is an ultrafilter located inside the body housing of the filter that contains a membrane of hollow fibers. The hollow fiber membrane is similar to those used by municipal drinking water and wastewater treatment plants.
The third stage of filtration is the removable carbon filter mouthpiece which is the outlet of the filtration system. The addition of the carbon filter to the filtration system is an added bonus as carbon filters are great for removing pollutants.
The Survivor Filter is a cleanable filtration system so you can take it apart. The main components include the bottom cap (cotton prefilter pad), body fiber filter (ultrafilter) and the mouthpiece (carbon filter).
Disassemble and reassemble takes only a couple of minutes. All three filters are replaceable, including the cotton prefilters (six of which are included when buying this filter).
The idea behind the Survivor Filter is a versatile way to filter water on the go. You can use the Survivor Filter as a straw filter, or you can attach it to a collapsible water bag or any plastic water bottle you have laying around the house.
Once you screw on the filter to the bottle, the idea is to use your own mouth suction while squeezing the water bottle to push the clean water into your mouth. While sucking water, the plastic water bag/bottle doesn't suck the water back out with the opposite pressure, which is a good thing.
The Survivor Filter is good all-round personal filter that can filter up to 1200 litres (265 gallons) of fresh water. This means if you filter 3 litres a day, you won't have to replace anything for at least 8 months.
Being so small and compact, the Survivor Filter doesn't take much room in a get-home bag. It only weighs 3.5 ounces and measures 7-inch long by 1-inch wide. The plastics used (including the collapsible bag) are BPA-free.