SteriPEN Ultra Water Purifier Review

Steripen Ultra

Using a Steripen Ultra water purifier will remove all contaminants, without the use of chemicals. A normal water filter will only remove waterborne bacteria and protozoa, but not viruses.

Steripen Ultra FAQs

Steripen Ultra will combat all three microbes that could be lurking in the water you’re about to drink. That also includes chlorine and any harmful metals that can’t be seen by the eye. 

Without a water purifier, you can’t guarantee that your water is pure and fresh. Especially if you’re out on a hiking trail or camping out and have no access to safe drinking water.

Yet, all you need to do is carry around a Steripen Ultra, and you can be confident all your water will be safe to drink. In this review of the Steripen Ultra water purifier, you will soon understand why you need this little gadget on your adventurous travels.

SteriPEN Ultra Features

Size7.3 x 1.3 x 1.6-inches
Power1 USB Rechargeable Lithium Polymer battery included.
Treatment Volume15000-liters of water.
CertifiedWater Quality Association (WQA) standards.
SteriPEN Ultra Specs

When you’re traveling, there’s one important item you should always take with you, and it takes up very little space in your luggage. This small gadget means you can be sure that the water you’re drinking is completely safe, anywhere, anytime.

No more iodine tablets to clean your water. Let the Steripen Ultra kill 99.9% of bacteria and viruses instead. This mobile water purifier works by using UV rays. 

What’s more, you can simply pop the charger into your USB port for recharging the battery-operated water purifier. Battery and charger cable is provided.

One-click will clean up to ½ liter of water in under a minute. Then add a further click for every extra half-liter of water. 

The unit has a self-illuminating OLED display. You can monitor the water treatment success rate, battery status and keep track of how many times you’ve used it. 

To learn more about all the great features of the Steripen Ultra, have a look at the online instructions leaflet:

How to Use The SteriPEN Ultra?

Remove Lamp Cover

Always remove the lamp cover first.

Activate SteriPen

When you first turn on, the green light will flash on for approx. 15-seconds, this is not a treatment. Before immersing in water, click on/off button once for each half liter of water you need to treat.

Purify Water

As the Steripen goes into the water, it will set the UV lamp in motion and the green light will flash. Stir the Steripen around in the water to mix it up a little.

Know When The Process is Done

Once the purification is complete, the green light will stop flashing but remain on. You will also have a smiley face in the OLED to indicate your water is ready to drink. Any red lights indicate battery warning, so don’t drink the water as it will not be properly cleaned.

Switch Off and Dry 

When finished, dry the lamp section and replace the lamp cover for protection.
If you want to see the Steripen Ultra in action, then watch the Steripen Ultra instructions on their own video below.


The older version of this model is the Steripen Freedom. Whilst it was lighter in weight, it could not perform as many water treatments. The newer Steripen Ultra is also less expensive, even though it’s the updated model.

The weight difference is because the Ultra has a better battery life so the battery is most likely slightly heavier.

The Steripen is quite a unique piece of life-saving equipment. It can simply be inserted into your water bottle, so long as the bottle has a wide enough opening.

Have a look at our CamelBak insulated water bottles. They are a perfect fit for the Steripen, with the lid removed.

If you’re planning an outdoor expedition, then you may also want to take along a good hiking backpack. We’d like to help you plan this. That’s why we’ve reviewed the Thule backpack.

Including a Steripen Ultra on any journey that you’re planning, is not only a sensible option but could potentially save your life. Particularly so, if you’re going on an outdoor vacation. Clean drinking water is vital for your health.

Many hikers have used other water filters, such as the Wild Peak straws. They can’t guarantee to kill viruses, only the waterborne bacteria, and protozoa. If you’ve read our article on germs in water, then you’ll understand why you’re better off taking along a Steripen Ultra. This is the only way to be confident your drinking water is fully for sterilized.

This article was last updated on November 28, 2022 .

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