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SteriPEN Safe Water Purifier System

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  • Safe Water system includes the SteriPEN Classic purifier, water bottle prefilter, 1-liter BPA-free wide-mouth water bottle, SteriPEN carrying case and instruction manuals
  • Ultraviolet (UV-C) light rays safely sterilize clear water by destroying 99.99% of viruses, bacteria and protozoa, including Giardia and Cryptosporidium
  • SteriPEN protects you from risks that cause botulism, cholera, dysentery and typhoid, just to name a few
  • But if clear water is not available, no worries—the SteriPEN 4-micron prefilter clears particulates and debris from water
  • Prefilter fits the included Nalgene BPA-free water bottle and other bottles with 63mm wide-mouth openings; pour source water through filter, and clean water enters bottle
  • Then use the SteriPEN purifier to treat the water; just press a button and gently agitate the water with a quick stir
  • SteriPEN purifies 16 fl. oz. of water (cold or warm) in less than a minute or 32 fl. oz. in a minute and a half
  • Small size fits most containers—use it in cups, mugs, water bottles and canteens
  • SteriPEN turns itself off once ultraviolet treatment is complete; can be used up to 8,000 times!
  • Watertight seals keep water away from the electronics; rubberized inset grips for secure handling in wet conditions
  • Low-power indicator tells you when batteries need replacing; twist-off cap for easy battery access
  • Long used by municipal water districts and bottling companies, low-level UV-C light treats water safely, and unit's light will not damage eyes or skin
  • Purify 200 glasses with 4 lithium AA batteries (batteries sold separately); SteriPEN does not recommend the use of alkaline batteries, as they provide very few treatments
  • SteriPEN recommends the use of name-brand lithium or nickel-metal hydride rechargeable batteries
  • Average weight of purifier is 6.4 oz. with lithium batteries; weight empty is 3.7 oz.
  • Only use SteriPEN independent of prefilter when clear water is available, as cloudy, sediment-laden water hinders effectiveness

Since late 2008, all SteriPEN water sensors feature twice the electrode voltage of older models. The increased electrical current flow allows proper function in water with low conductivity such as snowmelt and even mineral-free distilled water.


Item 784449

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SteriPEN Safe Water Purifier System Specs
Best use
Ultraviolet light
Protozoa, bacteria and viruses
Not applicable
Not applicable
32 oz. per 90 seconds
Not applicable
7.6 x 1.5 x 1.5 inches
22.8 ounces
Filter type
Filter medium
Pump force
Pump strokes per liter
Housing material
BPA free
Field cleanable

SteriPEN Safe Water Purifier System

Loading Ratings & Reviews...

Rated 3.3636/5 based on 11 reviews
Rated 1out of5
by fromOne big problem I have tried this product twice and had the same problem both times -- after about 2 days of using it, it starts turning itself off after just a few seconds in the water, and then signaling that it didn't run long enough to adequately treat the water. Kind of a problem for this to happen in the backcountry. At first, I thought it was a short, so I exchanged it, and someone else told me that this happens if you don't dry the device between uses -- particularly the two metal prongs that detect when it's in water. I tried that when the second one had the same problem, but wiping it with a t-shirt or towel wasn't good enough. It only started working again if I let it sit in the sun for 30 minutes, which doesn't really work if you're not planning a 30-minute trail break and doesn't work in any case if you're trying to fill multiple bottles. I returned it for a nice small simple pump and I'll stick with that until this technology evolves to the next level where basic problems like this are fixed.
Date published: 2010-09-10
Rated 1out of5
by fromBe Aware I own one older black and yellow steripen and it works fine. I bought one of the classics for my wife with the prefilter. The Prefilter is designed to contact the flange on the included bottle, or any nalgene bottle. That is so if you submerge the bottle in a source, it will keep dirty water from contaminating the threads of the bottle. The Pre-Filter did not touch the flange, and would have contaminated the threads, so, I did my 1st exchange. On the second one the filter did not touch the flange either, and the lid of the steripen was missing the contacts for the battery, so I exchanged it again. This time, when I opened the package, I found it had already been opened, and the english strip of instructions was cut off and missing, and the lamp only lit in half of the tube. And, the prefilter still did not touch the flange. I guess I will return this and get a pump for my wife. That and some pills will at least give safe water. Recap, 2 of 3 would not light fully, and 3 of 3 would have contaminated the threads if used as per the instructions. (I used fresh lithium batteries)
Date published: 2011-05-24
Rated 2out of5
by fromWork well , for a while Worked well until it didn't. Failed while on a 14 day trip into the North Cascade Nat. Park. Started getting red flashing LED error messages. No go after that. Put in fresh batt.'s and cleaned... Nothing. Took back to REI got $ back. Don't use as only way to filter / decontam. water on a trip.
Date published: 2011-02-27
Rated 4out of5
by fromGood, but not for all situations This isn't a perfect water purification system, but how/when it works, it is fantastic. Con: For the most part I use a 2 liter bladder to carry my water. This only filters 1/2 or 1 liter at a time, meaning I have to carry a bottle just to pour into my bladder or only use bottles. Con: It runs on 4 AA batteries which are marginally heavy and bringing a backup set is highly recommended. The problem is that on cold days/nights, the batteries lose effectiveness, and the blinking light will indicate that the process can't be completed. You have to make sure the batteries are warm before using this, otherwise you'll have a panicked, cold-handed morning. Also, I haven't used the pre-filter on the bottle with actual dirty water yet, but I imagine if you're really in a bind and have to use stagnant water (I've been there, but with a proper filter), you'll feel uncomfortable about using this and the water won't taste very good. That is why I hesitate taking this on some hikes and opt for my pump-filter instead. Pro: When you filter a liter of water in a few seconds without any tiresome pumping, aggravating cleaning, frozen hands, or malfunctioning filter, you really appreciate what the SteriPen has to offer. And if you're traveling in developing countries, this certainly comes in handy.
Date published: 2010-03-18
Rated 4out of5
by fromReassuring but tricky at times Doesn't filter out particulates but irradiates the water to kill any bacteria that may be present. It is a nice reassuring device when your not sure of the water quality. It can be a little fickle at times with its readings and all but it is fast and works well. Combine this with a filter and your set anywhere.
Date published: 2011-02-03
Rated 4out of5
by fromSo far So good Used mine twice for weekend backpacking trips with NO problems and didn't get ill (lake and stream water). It's electronic so there is a chance of failure and I wouldn't trust it for any long trips myself without additional filtering/boiling/iodine. But for 1-2 day trips test it before you go (as you should for all your gear) and you should be fine. It's no heavier than any other system and is very compact.
Date published: 2012-05-08
Rated 5out of5
by fromEasy I have used pumps and pills in the past. I found the UV pen easy to use and very quick. I can't see hiking without it.
Date published: 2009-11-10
Rated 5out of5
by fromWhat a deal I used the Steripen on a 6 day 5 night hike thru the Grand Canyon. I had treated water on several days but had to use the Steripen on several occasions and had no problems what so ever. Just make sure you follow all the directions on cleaning the outside of the bottle after treating to avoid contact with the untreated droplets on the rim. I also treated some water for others on the trail when they ran out and you should have seen their amazement of the speed and quality of the Steripen :-)
Date published: 2010-04-09

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