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SteriPEN SteriPEN Adventurer Opti

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    44 Reviews


    Pen mightier than bacteria.

    Destroy harmful waterborne bacteria in your water with the Hydro-Photon SteriPEN Adventurer Opti. The SteriPEN uses UV light to kill giardia, cryptosporidium, bacteria, and viruses in just a few seconds, so you can stay hydrated on the trail without having to worry about getting sick. And at a scant 3.6 ounces and 6 inches long, the Adventurer Opti won't weigh you down or use up a ton of valuable pack space.
    • Lightweight SteriPen purifies water on backpacking trips
    • Stir UV light in 1 or 1/2 liter of water for 90 seconds
    • Destroys 99.9% of viruses, bacteria, and protozoa
    • Runs on two included CR123 batteries
    • Replaceable lamp works for 8,000 treatments
    • Item #HYD0017

    Tech Specs

    Purifying Element
    UV light
    Lamp Life
    8,000 treatments
    Claimed Weight
    with batteries 3.6 oz
    Recommended Use
    hiking, camping
    Manufacturer Warranty
    limited lifetime

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Only a couple Ounces

    • Familiarity: I've put it through the wringer

    Small, simple, and handles viruses too! If getting water from springs and mountain streams, this is the device to take. Great option for international and local adventures alike.

    Awesome buy!

    • Familiarity: I've used it several times

    I would highly recommend this to anyone who is looking to get a small convenient water treatment device. It is easy to use and works like a charm. I used this for the first time a couple weekends ago down in Escalante and it was perfect for the trip. Let me know if you have any questions on this or any other water treatment devices we carry.

    drink up

    • Familiarity: I've put it through the wringer

    This water treatment device is small and simple to use. I have used it with and without my filter while camping/backpacking and it is the 1st thing I pack when traveling internationally. I have/will gift this many times over. The battery life has varied quite a bit so I suggest buying backup batteries just in case.

    A must for backpacking

      A quick and easy way for safe drinking water. Just dip into a naglene bottle, swirl until green light goes off, and its ready. I used it on a Salt Creek in Canyonland NP and I'm didn't get sick. It must be working.

      Easy stuff!

      • Familiarity: I've used it several times

      I like this SteriPEN for all of the same reasons as everyone else. Its small, light weight, and is really easy to use. I've used this baby over a handfull of times now and it never fails to impress the group I'm traveling with. On my most recent trip, it was able to suffice the needs of 3 people on a 5 day trip with a single set of batteries.

      never fails

      • Familiarity: I've put it through the wringer

      i have used the steripens in asia for months at a time. this year i am working with disaster relief in nepal. the villages are a are the water sources. there is more garbage and s-h-i-t around than there ever before and i am eating, sleeping, and drinking water in the thick of it daily. once again...6 weeks in and not a hitch or a hiccup with water issues. i didnt notice the new pen is not a double aa so i didnt bring back up batteries. so, take note of this.

      Can't get much easier than this!

      • Familiarity: I've put it through the wringer

      Once you know the specifics of using the Adventurer, it can't get much easier. I've taken it on many trips as a precautionary measure, as well as my main filtering source on backpacking trips.

      It's never let me down, and I've never gotten sick.

      Can't get much easier than this!

      Big improvement over the original

      • Familiarity: I've put it through the wringer

      I've had this little guy for about a year now. I had the original model SteriPen that I used for a few years and this one is lighter, sleeker, more rugged feeling, and seems to have better battery life.

      There are certain times where a filter is still a necessity or just more practical. Murky water and big groups, to name a few - even SteriPen freely admits this. But, there's a ton of situations where this thing is perfect. I love, love, love this thing for long trail runs in the mountains. Small enough to fit in a running vest or even most lumbar packs. No more choking down chemical treated water. Also great for general day hikes and short solo/duo backpack trips. For longer trips, especially if there's more than one person, I still think a filter is more practical. You may be disappointed in the SteriPen if you buy it as a replacement for a filter - but if you look at it as a different sort of water treatment device altogether, it's brilliant.

      Great Backpacking Tool

      • Familiarity: I've put it through the wringer

      I've used SteriPENs for a long time, but recently upgraded to this model. Simply put, I recommend going with this model over the cheaper alternatives for several reasons: size, battery life, battery type, and weight. It's smaller than many models, which makes a big difference when packing for a trip. I keep mine in a shoulder pocket on my pack so that I can easily use it without unpacking my bag. Next is battery life and type. It's more efficient than cheaper models and you don't have to use clunky AA batteries. This takes two small CR123 batteries, which are both lighter, and seem to last longer. I previously had the SteriPEN Photon Traveler and it requires 4 AA batteries -- it's heavy as hell! Bottom line, if you want a SteriPEN that's small, durable, and efficient, choose the Adventurer. Also, it works well with hydration bladders and water bottles. I've noticed it's a little awkward using this in a bladder because the light becomes hard to see (so you don't know if it's on or not). It's easy to find out, but it's still a little awkward.

      Excellent product

      • Familiarity: I've put it through the wringer

      If you're in an area with readily available water sources, like the John Muir Trail, the SteriPEN series of products are the best choice for purifying water. Lightweight thru hikers swear by tablets, but you have to wait 20-30 minutes for those to do the job, and the water generally tastes bad because of the chemicals. The pen is a bit heavier, but well worth the slight penalty. I managed 7 days of use for 2 people on one set of batteries. Will not work as well in cloudy or muddy water, but you'd want to use a pump in those situations anyway.

      best water-treatment system!

      • Familiarity: I've put it through the wringer

      I've used several different treatment/filtering systems ranging from UV, to filters to chemicals, and his is my go-to method for sure! I Love this thing when it comes to a clean mountain creek, or babbling brook. The down side of this light is that if the water tastes bad, this won't change anything, and it requires the use of CR123 batteries which can be hard to find and slightly expensive but all in all it is worth it! I would highly recommend this to friends and would replace it instantly if it was lost, stolen or damaged beyond repair! LOVE IT!

      Yeah, It might look clean enough.

        I got a new perspective being in a large group of people hiking and climbing on Rainier. I am like a camel and I seem to keep my fluids inside me. Or I sweat them out. I was amazed how much people pee everywhere. Yeah, that stream at Pebble Creek coming out from the Muir snow field looks like it would be fine to drink from without treating. Not a chance in hell Batman. I saw more people peeing all over the place just a stones throw away from the stream. I am also pretty sure I saw a marmot intentionally peeing and defecating upstream from a Chinese family taking sips directly from it as they took a break from their marmot molestation photo shoots. Payback is a bitch.

        Yeah, You need to treat your water.

        This steri pen is so quick and easy to use. Are there still some parts per million pee in your water? Sure. But what are you gonna do? I saw pee stains all the way up Rainier and the very top is like a volcanic pee trough.

        Folks, you are drinking someones or somethings pee one way or the other.

        I prefer this one to the classic. Not as big and clumsy feeling.

        SteriPEN Opti vs Classic

        • Familiarity: I've put it through the wringer

        Battery Life:

        I have used the Adventurer Opti all summer long and just had the battery run out on my last trip. I typically use the Adventurer Opti 1 to 2 days a week filtering about 2 liters per day. I would say if you're an avid outdoor junkie who gets out every week than you would only need to replace the battery in the Opti every 2 months. I've used the SteriPEN Classic for about 5 years and the battery life is roughly twice as long when using high quality lithium AA's. SteriPEN has a comparison chart with number of treatments per charge (.5L) but I always do 1L increments due to using a 1L Nalgene. Even in .5L increments the chart does show the Classic having twice the treatment cycles per charge, confirming my real world experience. It shouldn't be a surprise that the Classic has twice as many cycles per charge because the Classic uses 4 AA batteries while the Opti uses only 2 small CR123 batteries.

        Durability and Use:

        I've used the Classic for 5 years and haven't had a single issue and have only used the Opti for 3 months now. The biggest difference comes in at length and weight. Opti is about 6 1/4 inches long with 4.5oz trail weight (batteries and case). Spare batteries only weigh 1.1 oz because the Opti uses CR123's. The classic comes in at 7 3/4 inches long and 6.6 oz trail weight. Spare batteries weigh 2 oz due to the 4AA's. While the Opti is a little less convienient to use in the field, the weight savings and much smaller design has made me keep coming back to the Opti.

        ***The extra 20$ for the SteriPEN Adventurer Opti is worth the cost as it retains most of the great features of the classic but in a lighter, more compact design. ***

        Complete comparison of the Opti and classic at:

        SteriPEN Opti vs Classic

        I Love this thing

        • Familiarity: I've used it several times

        Used this all summer long and never got had an issue with sickness. Much better than pumping. 90 seconds gets you a liter of water. I carry an extra set of extra batteries as a backup but made it through one season without burning up batteries. Its not cheap but the weight and time savings are well worth it In my opinion

        Game changer; poor battery design

        • Familiarity: I've put it through the wringer

        This thing is a game changer for all my climbing/backpacking expeditions. Lightweight, fast, allows me to carry very little water weight when in areas with water (which are plentiful in the tetons). Only clear flaw is that the batteries are expensive, rare, and you have to take them out of the device after each use to maximize their lifetime as the life is unpredictable. carry an extra set or other purifier for backup. I've needed it.

        When packaged for retail the device comes with a little piece of plastic just inside the battery cap between the battery and the connector. It serves as an insulator, breaking the circuit, in order to avoid natural battery draw while on the shelf. I simply saved that piece and store my Steripen that way. I lost the plastic piece at a campsite once but I just cut a piece out of the bottom of a 20oz soda bottle in a similar shape to serve the same purpose. I've had it in storage for a few years and the original batteries still work great (though I do have a back up pair as a just-in-case).

        Unanswered Question

        What is the warranty on this? The tech specs on Backcountry say limited lifetime warranty, but the information on the manufacturer's website says 3 year warranty.

        What is the best way to deal with the problem of untreated water on the threads of a bottle that has been sterilized by the pen? I have been using an msr miniworks for a long time now and am about to switch to something lighter. I'm down to either the steripen or the sawyer mini. Suggestions and anecdotes are welcome.:)

        Hi Phil - SteriPEN recommends wiping the water around the threads of the bottle. If you dry the area we find you can safely consume from the bottle you treat the water in. Please feel free to contact if you have further questions about SteriPEN use and UV water purification.

        Hi Phil - SteriPEN recommends wiping the water around the threads of the bottle.  If you dry the area we find you can safely consume from the bottle you treat the water in. Please feel free to contact if you have further questions about SteriPEN use and UV water purification.

        Is the steripen good for purifying tap water as well? I'm planning on doing some international travel and I'm considering getting a steripen to sterilize tap water to put in my camelbak. Any thoughts?

        Does the pen sterilize the cap/ the threads...

        Does the pen sterilize the cap/ the threads of a bottle? Do I need to even worry about that? I am use to bleeding the threads using tablets and and worried that I could get nasty bugs if the threads aren't disinfected.

        Best Answer

        No it would really only sterilize everything in the actual bottle but, not on threads of the bottle. To be truly safe you would have to find a way to get the "dirty" water in the bottle without spilling into the threads.

        What volume of water can this steri pen...

        What volume of water can this steri pen purify at a time? I'm wondering if I can use it to purify my 3 litter camel back bladder...

        Best Answer

        It actually mentions this in the Tech Specs on the left side of the page. It'll purify any volume, just takes longer for larger volumes. At 8 minutes per gallon, a 3L Camelbak bladder should take about 6 minutes to purify.

        It can in theory...but they don't really recommend it for any type of soft-sided reservoirs or for more than one liter at a time. It's a matter of submersion depth and efficiency. It's only tested and certified for volumes up to 1L.

        What are the chances of a AAA or smaller...

        What are the chances of a AAA or smaller battery source being offered? I noticed the Solar Recharger kit. Is that worth it?

        Anyone know where I can get a pre-filter...

        Anyone know where I can get a pre-filter for this? I see it mentioned in some of the reviews and I wouldn't mind finding something a little bit more refined than my sweaty bandana.

        Would this work with a 3L water bladder...

        Would this work with a 3L water bladder if I ran it 3 times while the bladder was full?

        Best Answer

        This is really not designed that way. It doesn't work because there is no way to isolate the sterilized water from the nonsterilized. The UV works based not only on exposure time, but also the distance it must travel through the water. If you were to carry a 1 L bottle with you, emptying it after each treatment into the bladder, then you'd be good to go. Thats what I've done, and it does work, even if it is slightly more time consuming. Hope this helps!

        Will this product work with a platy soft...

        Will this product work with a platy soft bottle? I am afraid that the opening isn't wide enough to stir. It will likely work with a nalgene canteen bag but those are prone to leaking after a couple of uses (But they have a wide mouth!)

        To get around having to carry bottles specifically for use with a Steripen I simply took an old 2L Platy and cut off the top "half," so I was left with a plastic pouch that holds a little over a liter of water. I scoop that in the stream, stir with Steripen, and dump through a bandanna into my water bottles to get rid of any floating debris.

        So if I submerge my nalegene bottle in an...

        So if I submerge my nalegene bottle in an stream and then use the SteriPEN isn't there still bad stuff on the outside of my bottle, lid, and threads? Is this a deal breaker or can precautions mitigate this?

        Best Answer

        Hey Michael,

        First, we go back to the two bottle method. It works the best. There are a couple other ways to go about it though. With the SteriPen, you can carry some antimicrobial wipes that come in little packets (you probably know the ones I'm talking about from wilderness medicine)... dry the cap and threading before using them. Another method that works with the Micropur tablets or with iodine is called "threading". After you drop a tablet into your Nalgene, turn it upside down and slightly unscrew the cap until you see water seeping out. Tighten it back up, wait a few minutes, your threads are now purified. You're not going to need to worry so much about the outside of the bottle, so long as you keep it dry and don't bite your nails or something. I'll tell you where people get screwed up is in washing fruit, and brushing their teeth with untreated or unboiled water. Undercooking fish is another fun way to get the "trots". I'm also big on eating lots of yogurt with live cultures well ahead of time before heading south. Probiotics can do some amazing things for your GI tract and preventing problems.

        Thank you. I never thought of the wipes. I think that's my ticket. I have wanted a MIOX for years but I picked up the SteriPen yesterday. I'll have the tablets just in case. I have been pumping and boiling for so long that I am a little uneasy but the science is solid.

        I think the wipes or the two bottle method would seem to work. I would not rely on turning the bottle over and letting the cap leak. That works with Iodine because there is still iodine in the water in the bottle and that iodine purifies the threads. As I understand UV, once the light is off the treatment is over. I don't see the water itself has any residual treatment capacity to purify the lid or threads.