This was the absolute BEST thing we purchased for our recent Everest Base Camp trek. It worked like a charm, and we used it multiple times per day. We never had to purchase bottled/boiled water. Another great thing (depending on where you are at) is that the SteriPEN doesn't change the taste of the water. That was great up in the Himalaya (Kathmandu was a different story).

I really wanted to get the USB rechargeable SteriPEN. Although it would have been perfect for camping, it was going to be a pain on our trek. That's why we purchased this version. We went through 2 sets of batteries and we were on our 3rd. It functioned perfectly; we never had an issue.

This also works VERY fast as opposed to iodine/chlorine tablets. Those can take up to 4 hours to kill cryptosporidia/giardia. The SteriPEN "kills" everything in 90 seconds. Granted, that's "per liter", but it's still a lot quicker.

The only downside I can think of is "one liter at a time". It worked great for 2 people. I would certainly look for some kind of gravity device for large groups (not to mention you "only" get ~50 liters on new batteries).

EDIT: 3/29/2016

I've had this pen for almost a year now (can't believe it's been that long since I was in Nepal). It's still holding up to a 5 star review. We've since taken on a couple of trips (one time to Mexico and one time to Guatemala).

After reading some of the other reviews, I feel like I should mention that this works best with 1 liter, wide-mouth bottles. I actually purchased a Camelbak Chute (CamelBak Chute Water Bottle, Bluegrass, 1-Liter) to go along with this particular SteriPEN (and I needed a new water bottle anyway). You can treat less than 1 liter, but you should never treat more than 1 liter at a time (and no ice). For example, you could treat a glass of tap water (as long as it's deep enough to make contact with the contacts).

The SteriPEN never reached the bottom of the Chute. However, there was enough room to agitate the contaminated water by sticking the pen down in and then swirling it around. All I can say is that neither my wife nor I ever got sick using this system.

Great product, compact and easy to use

A very efficient, effective way to sterilize water when hiking. A little pricier than many filters, but you don’t have to worry about a clogged filter slowing down the sterilization process.

I used this in conjunction with my Sawyer water filter at the start of my 2021 AT thru-hike. I wasn't comfortable with treating water yet and I wanted maximum pathogen killing. I never used it by itself, as even if it did kill the pathogens, I didn't want to drink sediment water. Does it work? Well...I can say that in conjunction with my Sawyer, I never got a water borne illness. Eventually, I ditched it to shave grams. It's small, portable, and light weight. It's probably not necessary in North American mountain streams, but if I went overseas, or sourced water from a cattle trough or poo pit, I would use it.

Easy and doesn’t give water a taste

I just got this for Xmas so obviously I haven't used it on the trail yet, so I'm basing my review on my at-home evaluation.

As a multi day backpacker/hiker, who has painstakingly filtered gallons and gallons of water in all conditions, this little gadget is one of the most exciting things I've ever seen.

I did a lot of research before requesting this model. It comes with the lithium ion batteries (included) as opposed to AAs or triple As. If you're a gram counter like me, this is a big deal. They last a long time and weigh almost nothing.

The whole unit feels like it weighs almost nothing. I think it's 3.6 oz. and it comes in a great little nylon pouch that has a Velcro fastener loop that can go on a belt or backpack.

All you have to do is turn it on, hold the wand part in a liter (or half liter) of water for 48 seconds, stirring it, and you're good.

I did get the filter option (sold separately) to filter out larger particulates, dirt, leaves, etc.

Filtering water is one of those things you just can't avoid if you're in the backcountry for any amount of time, but this is a game changer. In terms of the weight and amount of equipment you have to carry (that alone is worth it to me), and the amount of time you have to spend doing the actual filtering. Compared to chemical treatments (20-30 minute wait and funny taste), expensive filter options like the Katadyn- which is great quality but takes up space and is heavier- even my trusty Sawyer Mini- and you still have to do all that pumping- this is a fantastic option to have.

I would also tuck this into my luggage if I were traveling to a foreign country. It would have given me such peace of mind if I had this when I was in Mexico.

Giardia and other assorted water nasties are no joke- they can more than ruin a trip. It's tempting sometimes to skip the filter when water "looks ok" and you're on a schedule. This gizmo makes it so you can make your water safe in under a minute!

I will edit this review once I get outside with the SteriPen, but so far I am impressed.

After careful consideration, I decided that this we the very best water treatment solution for winter backpacking. Filters can freeze, chemical treatment reaction rates decrease due to the lower temperatures, and boiling is not practical from a time and fuel standpoint. This however is not affected by lower temps, and electronics are something that can be managed. I chose this model of SteriPen because it is both compact and has removable batteries, so I can bring spares. It is small enough that it lives in a pocket of my mid-layer throughout the entire trip, even at night. I typically use 1L Widemouth bottles and this works perfectly with those.

Found batteries, had to replace them as they died only 7 or 8 weeks of use.

$8.00 each at the dollar store, horrendous!

Unit doesn't even work that well when the batteries were good.

Too much money for a unit that hardly works!!

Hat im Urlaub super funktioniert.

Für 14 Tage Wasseraufbereitung (ca. 7l pro Tag) haben wir 2 Sätze Batterien benötigt.

Requiere el uso de unas pilas difíciles de conseguir, y la tapa se cierra con un tornillo que probablemente se rompa. Afortunadamente hay otro modelo de esta marca que funciona con pilas AA.

Una de las mejores opciones para purificar agua si viajas ligero. Utiliza pilas comunes, deben de tener buena carga para ser utilizadas con este SteriPen. Yo no recomiendo que se use la lámpara como linterna por diversas circunstancias inherentes a usar una luz de este tipo. Es fácil de usar y sugiero que se utilice con recipientes de "boca" ancha para poder utilizar bien el SteriPen. Este purificador vale la pena comprarlo, por funcional y por su eficacia al usarlo.

Je l’ai utilisé sur 70L d’eau de rivière en cumulé pour le moment et je n’ai pas été malade. Il faut le coupler avec un filtre cependant. Le fonctionnement est simple, cependant il est un peu difficile de voire les led indiquant l’état du traitement de l’eau quand on est en plein soleil.

Einfach toll bei reisen ein sicheres Gefühl zu haben. ✌️🧳