Gear Review: SteriPEN Adventurer Opti with Solar Charging Case

I’ve always been a big supporter of MSR’s water filtration products.  In fact, I still own and use an older model from the 90s.  And it works great!  But what I’ve been suggesting to fellow snowshoers and hikers is to use the SteriPEN in conjunction with a filtration system – especially on long backcountry trips.  

If it comes down to it, use the SteriPEN on its own.  While it doesn’t filter precious H2O, it purifies it with the help of ultraviolet (UV) technology.  The UV light eliminates more than 99.9 percent of bacteria, viruses and protozoa that cause water-borne illnesses – specifically giardia lamblia, the most common spoiler of backcountry treks.  

“The SteriPEN.”  It sounds ominous and menacing, doesn’t it?  Say it.  SteriPEN!  Of course, it’s only threatening to viruses, protozoa and diarrhea-inflicting microorganisms.  And it was a welcome addition to my snowshoeing utility belt.  While most people think of purifying water in a spring/summer setting, the SteriPEN was essential during the winter.  

According to SteriPEN, “the Adventurer Opti, uses a revolutionary optical eye to sense the water. The patent-pending technology ensures safe use and provides purification in even the coldest of waters.”

So true.  

While some water filters (and possibly some purifiers) can’t sustain the same purification standards in cold water, the SteriPEN Adventurer Opti still manages to do the job.  

How do I know?  Well, let’s just say my digestive system still functions properly after using the SteriPEN multiple times throughout the winter – all while snowshoeing.  There’s nothing like cracking open an ice-covered river and collecting some frigid water in a bottle for an immediate refreshing drink (of course, 90 seconds after purifying it).   

It’s simple to use…

*To purify one liter in 90 seconds, take the SteriPEN cap off and press the button once (a green LED will flash to indicate that it’s ready)

*Immerse the SteriPEN’s optical sensor and stir to agitate the water (you’ll notice the UV light will illuminate to indicate it’s working)

*The green LED light will reappear when the water has been purified.  A red LED light indicates a failed purification attempt. 

*If there are particulates in the water, try using a coffee filter, bandana or a SteriPEN Pre-Filter to eliminate unwanted gulps of nastiness

*Remember to wipe the SteriPEN dry before stowing it

Beyond its water purification capabilities, the SteriPEN can double as a flashlight.  The “flashlight mode” – as it’s referred to – is activated by pressing and holding the button down for three seconds.  This is a great feature when trying to find your way around a dark tent or backpack.  It’s even better when trying to act like you’re wielding a rather short lightsaber and making nerdy lightsaber sounds.  Good fun.

Keep in mind, the SteriPEN can be purchased as a standalone product or it can be purchased packaged with a solar charger.  In my opinion, the solar charger is the way to go.  The SteriPEN can be stored in the solar charger case to help protect it from damage, especially if it’s your primary water purifying source on the trail.  But regardless, the SteriPEN is made to be resilient and tough.  And it doesn’t weigh a ton either.  

Of course, the SteriPEN is a powerful all-season water purifier.  Now that the hiking season is here, the SteriPEN is ideal for one-day treks or multiple-day backcountry adventures.  Don’t leave home without it!  And don’t leave home without charging it first.  That’s a mistake you won’t make twice, believe me.

Additional features:

*Solar panel recharges one double-cell battery in two to five days

*Battery can be recharged via the included plug-in power adapter in four to six hours

*Empty charging case weighs 6.8 oz.

*Weight: 103g/3.6 oz. with battery

*Size: 15.5cm. (6.1in.) x 3.3cm. (1.5in.) x 2.2cm. (1.0in.)

*Battery: Uses two CR123 batteries (included)

*Battery life: Disposable – 100 treatments (16oz./0.5L); Rechargeable – 40-50 treatments (16oz./0.5L)

*UV Lamp Life: 8,000 treatments (or 2,000 gallons)

For more information on the SteriPEN, visit and

To purchase the Hydro Photon SteriPEN Adventurer Opti with Solar Charging Case, click here.

About the author

Ryan Alford