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SteriPEN Adventurer Opti Water Purifier

    SteriPEN Adventurer Opti Water Purifier

    The SteriPEN Adventurer Opti water purifier is equipped with a new optical water sensor for reliable performance so you can enjoy clean, purified water on the go. See details

    • $89.95

    Item # 799003

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    The SteriPEN Adventurer Opti water purifier is equipped with a new optical water sensor for reliable performance so you can enjoy clean, purified water on the go.

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    The SteriPEN Adventurer Opti water purifier is equipped with a new optical water sensor for reliable performance so you can enjoy clean, purified water on the go.

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    The SteriPEN Adventurer Opti water purifier is equipped with a new optical water sensor for reliable performance so you can enjoy clean, purified water on the go.

    • From 2011 Backpacker Editors’ Choice awards: “Our testers have tried every water-treatment method available, and for most trips and conditions, this one beats them all”
    • SteriPEN Opti features an optical water sensor that detects whether or not the device is in water and only allows the UV lamp to activate when the SteriPEN is immersed
    • After pressing the button to activate the SteriPEN, immerse the lamp and optical sensor; the UV lamp will then activate and emit UV light and visible blue light
    • Optical sensor doubles as a backup LED flashlight that can be handy when walking to the stream to get water; operate flashlight with SteriPEN cap in place to protect the lamp
    • Adventurer Opti requires no pumping, chemicals, test strips, extended time-keeping or filters; leaves no aftertaste, will not clog and does not require lubrication
    • Innovative SteriPEN system uses UV light rays instead of chemicals to purify water for drinking
    • Ultraviolet (UV-C) light rays safely sterilize clear water by destroying 99.99% of protozoa (including Giardia and Cryptosporidia ), bacteria and even viruses
    • 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 when used properly
    • SteriPEN protects you from risks that cause botulism, cholera, dysentery and typhoid, just to name a few
    • SteriPEN Adventurer Opti is simple to use: just press a button and gently agitate the water with a quick stir
    • 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; carries easily in a shirt pocket
    • SteriPEN Adventurer Opti turns itself off once ultraviolet treatment is complete; light source can be used up to 8,000 times!
    • Watertight seals keep water away from the electronics; rubberized coating ensures secure handling in wet conditions
    • Low-power indicator lets you know when batteries need replacing; screw-off cap permits easy battery access
    • Use only on clear water, as cloudy, sediment-laden water hinders effectiveness; FitsAll prefilter (sold separately) clears particulates and debris from water
    • SteriPEN Adventurer Opti includes 2 nonrechargeable lithium CR123 batteries; SteriPEN does not recommend the use of alkaline batteries, as they provide very few treatments
    • SteriPEN recommends the use of name-brand CR123 lithium batteries with a capacity of 800 milliamp hours (mAh) or greater, such as Duracell, Energizer and Panasonic
    • SteriPEN Adventurer Opti water purifier includes a neoprene carrying case with belt loop

    SteriPEN water purifiers meet U.S. Environmental Protection Agency standards for microbiological water purifiers and have been independently tested by the Oregon Health Sciences University and the universities of Arizona and Maine. For complete test results visit

    Items with a lithium battery can only be sent via Standard ground shipping, and can't be shipped to P.O. Boxes, Alaska, Hawaii, U.S. Territory, APO/FPO, or International addresses.


    Item 799003

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    SteriPEN Adventurer Opti Water Purifier Specs
    Best use
    Ultraviolet light
    Protozoa, bacteria and viruses
    Not applicable
    Not applicable
    32 fl. oz. per 90 seconds
    Not applicable
    6.1 x 1.5 x 1 inches
    (With batteries) 3.6 ounces
    Filter type
    Filter medium
    Pump force
    Pump strokes per liter
    Housing material
    Field cleanable

    SteriPEN Adventurer Opti Water Purifier

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    SteriPEN Adventurer Opti Water Purifier is rated 3.7667 out of 5 by 30.
    Rated 5 out of 5 by from Steripen Adventurer Works Well! I've had two of the Adventurer models and am buying a third. One stopped working after I dropped it four feet onto a tile floor--I blame myself for that. The second one worked for over a year before I somehow lost it! I used the Steripen backpacking on several trips and on an almost daily basis for sinus rinses at home. Never ran out of batteries in the woods (but you should carry spares just in case) and using it once a day at home the lithium batteries would last for 2-3 months. There's absolutely no issue getting the water into the bottle as one reviewer complained--just use your cookstove pot (the pot will disinfect when you heat it) if necessary. If you are super ultra-light you're going to carry tablets, anyway, but if you're using filters the Steripen is lighter and much less work (no flushing filters at home) at least in theory it is more effective. It doesn't work in muddy water but the water does not have to be perfectly clear. I do carry the pre-filter kit. Having experienced the "heartbreak of electronics" many times with other products I have been pleasantly surprised by how robust this one seems to be. I'll never go back to pumping a filter. I've used other models but the Adventurer is my favorite because of the LED water sensor (more reliable) and the flashing LED that helps you know it's working.
    Date published: 2014-04-08
    Rated 5 out of 5 by from Great product I am 52 years old and have been backpacking for nearly 40 years, mostly in the Appalachian Mountains, but some out West and overseas. Water treatment has changed a lot since I used drops of Clorox years ago! This little baby is easy to use, lightweight,and has not failed me in two years of use. I have taken it to numerous countries, and used it in dozens of water sources here in the States. No bleachy taste (tablets). Beats the heck out of pumping (and smaller than pumps, too). A great product whose price keeps dropping. I like it!
    Date published: 2014-04-14
    Rated 4 out of 5 by from Sterilization you can trust I bought this for a backpacking trip in Aravaipa Canyon, AZ. With constant creek water available, this product was a no brainer. I paired it with the company's pre-filter, and both worked great. I drank apx 12 liters using the SteriPEN and I trust it completely. It's function is intuitive, and it's construction durable. After sterilization, it gives a green light... like the Ghostbusters, "Light is green, the trap is clean"
    Date published: 2014-04-08
    Rated 5 out of 5 by from What's up with the haters - this is gr8! I've used this product in a number of settings. I used it on a 12 day backpacking trip in New Mexico and a 5 day backpacking trip in "The Bob" in Montana. It worked wonderfully for me. I found it to be reliable, I found the batteries to last sufficiently long. The 12 day trip consumed one set of spare batteries. I am not sensitive to these kinds of things, but I do have an observation about all the comments about the power switch. Yes it is true that it is difficult to turn on with gloves. In cold climates that could be a drag. However, carefully pressing on the button has not proven to be an obstacle for me. (50 year old average man). In regards to comments that the water tastes bad, this device does not filter anything so the taste of the water is not significantly impacted either to make it taste better or worse. The 90 seconds it takes to stir a litre of water can seem like a long time, but compared to other alternatives, like pumping the water through a filter, boiling the water or using purifying tablets, I find the steripen to be more convienent than these methods by a LARGE measure. I've seen other models that use "regular" batteries like double "A"'s, mine uses the CR 123 batteries. They last a long time and have not failed me a single time. I've used the older model and have personally observed that it consumes batteries faster and is "glitchy". Not so for the current model at least in my experience. In addition to the trips mentioned above, I've used it on several (4 -6) 2 - 3 day hikes on the AT. In every case it performed well. If you are in such a "rush" that taking the 90 seconds a litre or the attention to detail that requires you to accurately push a small button then this might not be for you. It is for me!!
    Date published: 2014-03-26
    Rated 4 out of 5 by from Have a Plan B I used this sterilization device for the first 130 miles of my Appalachian Trail hike. Then, one day, nothing but flashing red light. I put new fresh batteries in . . . still nothing but flashing red light. My Steripen was not working. No combination of fresh batteries would fix the issue. Luckily for me, I had a cell phone with a charge and was in a place about nine miles norht of the Nantahala Outdoor Center, where I got a cell signal. With a great deal of persistence, I was able to get through to the company. With an even greater deal of persistence, was able to speak to a tech. This process was entirely too time--and cell battery--consuming. In the end, however, the company that manufactures this product did replace my Steripen. However, had it not been for the fact that I had a back-up plan, I might have had to drink water that was not sterilized, which is not a good idea, though I know that some folks do it. I hope that the company has solved whatever the problem was that caused my Steripen to malfunction, but the fact that they replaced it for me shows that they are willing to stand behind their products. Had I not had this issue, I would have gladly given the product five stars. That said, nothing in life is guaranteed, save death and taxes. You should always have a plan B, no matter what it is you're dealing with.
    Date published: 2014-03-26
    Rated 4 out of 5 by from Great so far... First of all, I love this thing. It's a great solution to the filtration/treatment question. After seeing other hikers with this, I decided I had to get one. My old system involved getting out the "dirty" water bag, filling it, connecting the inline filter, purging the air from the line, then letting it drain into my "clean" bag in my pack. Then putting it all away. With this thing, I fill the bottle, uncap the steripen, and swirl for ninety seconds. Much faster, and no wet filters/bags in my pack. It's tiny, and the little case clips to a shoulder strap so you always have it ready when you cross a stream. The cons: 1. It's fragile. I havent dropped it, but it has a 2" glass bulb sticking out, so you do the math. 2. I like my hydration bag. With this, I would have to fill a liter bottle, treat, pull the bag out, dump a liter in, then repeat. I would use this where you know water is plentiful and you have a liter bottle easy to reach.
    Date published: 2014-03-26
    Rated 4 out of 5 by from So far so good! We used our new Steripen for two weeks of backpacking and day-tripping on horse-heavy trails, and stayed healthy. But it's not like we did a test with one of us drinking untreated water. The pen is light and fast and leaves the water good-tasting. The only down-side is that the indicator lights are unpredictable from time to time.
    Date published: 2014-03-26
    Rated 4 out of 5 by from Works for me I have used on 2 backpacking trips. Was using a pump before. Nice product. Works as advertised. Beats pumping. The indicator lights are hard to read if you are not in the shade, which is why I don't give it 5 stars, but this is by no means insurmountable (audible beeps would be nice). Batteries aren't cheap. You get (per the mfr) about 50 liters per set. I am not sure how this compares to the cost of replacing filter cartridges or using tablets/drops, but seems pretty similar. I have only used on clear alpine water sources, not murky water. Even for clear water, the prefilter is nice (also helps keep the bottle lid dry)
    Date published: 2014-03-26

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