Summary
The SteriPEN Adventurer Handheld Water Purifier is a portable water sterilizer that outdoor enthusiasts and travellers can use to turn any source of water into clean drinking water.
This compact water purifier uses powerful ultraviolet light technology to kill harmful microbes and other kinds of bacteria and viruses in a very short period of time. For instance, for half a liter container of water, 48 seconds of zap time should do the trick. On the other hand, for a liter of water, it takes twice as much time, or about 90 seconds. Backpackers can easily carry this given its small size and weight, which is just under 4 ounces (including batteries).
Carrying one water bottle and a fully charged SteriPEN would provide you with access to clean drinking water for most expeditions. Equipped with disposable batteries, the SteriPEN can easily handle 100 purification sessions for each pair of batteries. If you want to go eco-friendly, you can use rechargeable batteries instead. In this case, you can invest in the SteriPEN solar charger, which also serves as a padded carrying case. Charging time is estimated around eight hours, but the batteries run for another 50 to 60 purification sessions before the charge is drained.
For its price, the SteriPEN offers excellent value for money in a compact size. For voyages in which every extra pound counts, the SteriPEN is more practical to carry than a relatively heavy water filtration pump. For vacationers and hikers, this handy water purifier saves you and the environment the added costs of buying bottled water. All it takes is a source of clear water and a few seconds of zap time. Then, you can enjoy purified drinking water whenever you need it.
Product Snapshot
Amazon Price: $79.95
Amazon Ranking: 
Sample Customer Reviews
Some quotes from 24 reviews of the SteriPEN Adventurer Handheld Water Purifier on Amazon:
“Works great for backpacking”
“Excellent device for sterilizing water”
“Great idea. Works well and is not hard to use.”
Features
The SteriPEN Adventurer is a lightweight and compact UV water purifier that can annihilate 99 percent of harmful bacteria, viruses, protozoa, and other microorganisms, such as giardia that cause diarrhea. This handheld water purifier works fast as it can sterilize half a liter of water in 48 seconds and a liter in 90 seconds. All you need to do is fill up your water canteen or bottle from any clear water source, and zap it for a few seconds with the UV light from the SteriPEN Adventurer.
Compared to bulky water filters that comes with several peripherals such as tubes, filters, and pumps, the SteriPEN is more practical to carry in long distances because it only weighs approximately 3.6 ounces and measures 1.5 inches in width, 6.1 inches in height, and an inch in diameter.
This new model comes with an innovative optical eye that can point out clean water sources. For instance, most campers would think that if a stream of rushing water is clear, it is safe enough to drink from it. Unfortunately, in today’s environment, such is not always the case. Dangerous microorganisms from animal and human excrement can find its way to natural or local water sources, so even if the water is clear, it may not be free from harmful bacteria and viruses that causes gastro-intestinal ailments and illnesses. By inserting the SteriPEN into a container holding the water, the eye will indicate if the water contains harmful contaminants.
The SteriPEN is equipped with UV purification technology that destroys 99 percent of harmful microbes. During the purifying process, the harmful microorganisms absorb the ultraviolet energy from the light, preventing the cell enzymes to “read” its DNA. The absence of intact DNA makes the microbes unable to reproduce and cause damage or sickness.
The Water Quality Association (WQA) has tested the SteriPEN UV water purifier and it passed the US EPA Microbiological Water Purifier Standard. Thus, it earned the WQA Gold Seal for excellent water purifying products.
The optical sensor also serves as an LED flashlight. To activate it, you press and hold the button for a few seconds. This is useful when you need to take a night walk to your water source for a refill.
For added value, the SteriPEN user pack includes a pair of disposable CR123 batteries and a neoprene insulated case that comes with a belt loop for easy transport.
Tips for Using the SteriPEN Adventurer
The SteriPEN Adventurer can be used with water containers that have a diameter opening of 1.75 inches at least, or any wide-mouth water bottle. Make sure your water bottle is at least this wide to use with the SteriPEN.
When using the water purifier, always check the green and white indicator lights. After pressing the activation button, wait for a few seconds until the lights flicker. When they do, the device is ready to be put into the water and the UV light will turn on once it detects the water. Stir the water with the UV light until it goes off and the green LED light turns on. This means that the water is purified and ready for drinking. When done, wipe the UV light clean and put the lamp cap back.
Before heading out on an adventure, always check the batteries if these are completely charged or still usable. Better yet, if you are using rechargeable batteries, it would be advisable to bring along portable charges on the road for quick recharging times. Alternatively, the SteriPEN solar charger is a great option for those travelling off the beaten track.
Pricing
Amazon Best: $79.95
Manufacturer Direct: $89.95
Assessment
Pros
Using ultraviolet light, such as with the SteriPEN, is a good way to purify water. The process itself is effective and without side effects. It also does not use chemicals to alter the water properties, such as its pH level. And, best of all, it does not have any strange aftertaste.
The SteriPEN Adventurer is simple and easy to use. You don’t have to wait for a long time for the whole purifying process to take effect. It just takes a few seconds and the water is fit for drinking (without any chemical aftertaste).
Another big benefit of this water purifier is that it is tough built. It can withstand a few drops and slips and rough handling. Even its pouch is durable and made with quality. You can take the SteriPEN Adventurer anywhere, more so if you use rechargeable batteries and carry a solar charger.
Cons
One shortcoming of the SteriPEN Adventurer is that is there is no absolute indicator on the device if there indeed has been a change in the water’s purity. But, in all fairness to the SteriPEN, few if any, portable water filters provide any sort of indication of change.
Because of the SteriPEN’s unique design, it cannot be used on bottles with narrow necks or small openings.
Lastly, when used in broad daylight, it takes a while to see the blue light that comes on to identify that sterilization is underway. You might also be confused with the series of blinks and different lights. This may result to incorrect usage in terms of timing each purifying session. It is advisable to practice using the SteriPEN and try it out a few times at home.
Alternatives
MSR MiniWorks EX Microfilter
As an alternative to the handheld SteriPEN Adventurer, consider the MSR MiniWorks EX Microfilter (see our review here). This is a portable water filter that filters out impurities at a speed of one liter of clean water per minute. The MSR MiniWorks is also low maintenance because it can be cleaned several times without any adverse effects on the device. ($70)
Katadyn Pocket Water Microfilter
Another good alternative is the Katadyn Pocket Water Microfilter (see our review here). This is also a portable water filter, that is often considered the gold standard of water filters among serious adventurers and humanitarian workers. ($320)
Conclusion
The SteriPEN Adventurer Handheld UV Water Purifier is an excellent companion for international travelers and outdoor enthusiasts. It is compact, light and easy to carry on extended adventures. It provides chemical-free protection from a host of harmful microorganisms, like bacteria, protozoa and viruses. Plus, you don’t have to wait too long for clean drinking water as the sterilization process only takes a minute or two to purify water from unknown sources.