The Ultra SteriPEN is a unique purification rechargeable system that utilizes UV light. The wavelengths emitted decimate the DNA in these organisms, not allowing them to reproduce. While it does seem a little like magic, pressing a button, and waving a wand, this unit has a few shortfalls. While we appreciate its lighter weight, slim profile, and fast treatment time, we wouldn't usually reach for this filter simply because of its lack of reliability that is a result of it using a battery. This is an excellent option for international travel or for sitting by the beach at your favorite resort in Mexico.
SteriPEN Ultra Review
A UV purification system that eliminates the threat of viruses and other pathogens.
Price: $110 List | $79.93 at Amazon
Pros: Lightweight, rechargeable, waterproof, removes viruses and other pathogens
Cons: Finicky battery life, unreliable, small treatment capacity
Manufacturer: SteriPEN
Cons: Finicky battery life, unreliable, small treatment capacity
Manufacturer: SteriPEN
By Amber King ⋅ Senior Review Editor ⋅ May 6, 2019
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Our Verdict
Compare to Similar Products
Our Analysis and Test Results
This UV light purification system requires a power source and water to purify. It can immobilize bacteria, protozoa, and viruses with a simple whirl of the wand, just like magic. While we appreciate this technology, we question its reliability. It has a short battery life and has a reputation for not working at inopportune moments.
Performance Comparison
A look at what comes with the SteriPEN Ultra.
Water Quality
Almost like magic, you touch a button, swirl, and voila…clean water that is free of bacteria, protozoa, and viruses. The UV light sends out intense wavelengths that decimate these pathogens' DNA so they cannot reproduce. That means that even if they enter your system, it won't supposedly cause you any harm.
The SteriPEN Ultra uses ultraviolet light to get rid of harmful microorganisms.
Since this isn't a filtration system, it does not filter out particulates and sediment. If you plan on traveling where the water is full of sediment, consider a filtration system instead. Though, if you know that clear sources are what you'll primarily encounter, this unit should work like a charm.
Durability & Maintenance
This system supposedly can filter up to 50 liters per charge, though we noticed our battery running low before this claim, getting about half that, especially in colder weather. The company website says that one bulb can purify up to 8000 liters which we don't know is true or not.
SteriPEN offers both options that are rechargeable or with batteries. Depending on what you prefer, you should get the appropriate option. One of the most significant issues with this filter is reliability. We've experienced the SteriPEN glitching out on longer runs, leaving us without a water filtration system. If it's freezing, the battery will drain quickly. We also noticed that after several uses, the battery charge does not retain as it does at the beginning.
As a result of this lack of reliability, we can't wholeheartedly recommend it for extended backpacking trips. It's a good option where you can get back to a power source to the plugin. There are solar chargers that work nicely on the trail, but those require sun. If you are without that for a few days, you might get skunked. Even then, with a full charge, we've experienced the sad face for no reason, which left us frustrated and without clean water. Luckily we had a chemical treatment backup. Like everything electrical, it's not the most reliable in the backcountry and more suited for situations that won't leave you wondering if you'll survive or not.
Make sure you have access to a power source or you might find yourself without a purification system.
Treatment Time
This unit counts down your purification time. It takes 90 seconds and some swirling to purify one liter of water. There is also the option to do a half-liter which takes half the time.
The Ultra has simple directions on the unit, push the button once to treat 1 liter and twice to treat half a liter.
Weight & Packability
The SteriPEN Ultra is a meager 6.65 ounces including its squishy carry case. Of the SteriPEN models, it's the heaviest, but it's much lighter than pump filters that treat viruses. The profile is narrow, which fits nicely into a backpacking pack or even a running pack. It's a little large for ultralightweight missions that might go for 20+ miles, but, for a trail run where you need water on the go, it works just fine.
Relative weight with the case.
A look at relative size and profile.
Ease of Set-Up
The Ultra is very simple to use. Turn it on, place it in your bottle. Water retrieval depends on your storage container. If you are taking from a water source with lots of sediment, make sure to pre-filter your water or consider a filter instead.
Ease of Treatment
Treatment is also easy. Wait for 90 seconds per liter purified. Swirl it around. When you see the smiley face, your water is ready to drink! If you see a frowny face, it means either your battery isn't working, or something is wrong.
The Ultra takes 48 seconds to purify half a liter, which actually feels like a long time when you're standing there stirring the water around.
Value
It is pricy. Given that it's not super reliable, even though it does remove viruses and other stuff, it's not our first recommendation for most things. However, if you like the idea of it, and you'll be around power consistently, it is quite convenient, fast, and easy to use.
The smiley face on the Ultra makes tester Jessica Haist smile.
Conclusion
The Ultra does best for international travel or super short trips into the backcountry when it's not cold. This UV filter eliminates everything including viruses, but its short battery life and inability to treat large amounts of water does limit its use.
— Amber King