If you’re thinking of going to Mexico then you are going to need the SteriPEN. This is a seriously cool light-pen that you put in a container of water (up to 32 oz) and within 48 to 90 seconds you will have water free from the following items: Viruses, bacteria and protozoa–including Giardia and Cryptosporidium.

Great Product for frequent travelers and campers!, July 8, 2009
By Rogue (UT)

I purchased the SteriPen before moving to the mountains of China for 6 months. After doing the math, I knew that I’d be spending a lot more on bottled water than it would cost to purchase the pen. I was glad I bought it as I was able to use it on the tap water (which is undrinkable in China if you’re not a local whose body has adapted- unless it’s a major city like Beijing, and then bottled water is a must!) I also used it on the water that I had to pull out of a well when we had no tap. It saved me loads of money and didn’t alter the taste of the lovely mountain water like boiling or iodine tablets do. I was able to have clean water when washing my face and brushing my teeth in addition to having clean drinking water. And supposedly, it’s even safer than filtering and iodine. Filtering will not always remove various bacteria or diseases such as Yellow Fever, but all of that will be neutralized with the SteriPen. UV light is actually used in many water purifying centers.

A few tips though:

1. Use lithium batteries. They’ll last much longer. I brought 7 packs for my trip and only used half that in 6 months. If you’re going on a long hike, bring an extra pack of batteries- they’re not that heavy in comparison to a water filter and you’ll have a backup in case you need it.

2. Don’t pull too hard on the glass portion of it when drying it off. I noticed that I had a few problems with that because I was a little too rough on it. After I realized what I was doing, I was a little more gentle and it worked fine. But I’m surprised to hear that some people managed to break theirs, I kept mine in the cushioned pouch and it didn’t even get scratched.

3. Make sure you buy a water bottle with a wide mouth and measuring lines on the side. You’ll need the space to swirl the SteriPen around and you’ll want to know how much water you’re putting in the bottle.

4. If you’re pulling water out of streams, the SteriPen will not remove sediment, so bring something like pantyhose, etc. to filter out larger particles.

I did all of the above and didn’t get sick from the water even once while in the mountains of China for 6 months. Now that I’m back in the States, I keep it for emergencies and will be using it on my upcoming camping trip!

Product Description
Great for travel or an emergency-preparedness kit, this handheld water purifier destroys viruses, bacteria, and common protozoa. It weighs just 8 ounces with four AA, disposable batteries (not included) and purifies 16 ounces of water in 48 seconds, or 32 ounces in 90 seconds. The purifier employs ultraviolet light (UV) to destroy the DNA of microorganisms, making them unable to reproduce and cause illness. It’s effective against outdoor microbes like giardia and cryptosporidium; pathogens that cause diarrhea, dysentery, hepatitis, and Legionnaire’s Disease; household germs such as bird flu, E. coli, and salmonella; staph and strep; and natural-disaster risks like botulism, cholera, smallpox, and typhoid.

No pumping, no chemicals, no test strips, no timekeeping, no lubricating, and no replacement filters are required. All that is required is to push the water purifier’s button (once for 32 ounces, twice for 16 ounces), place the pen-like lamp in clear water, and stir until an indicator light turns green. Water has no aftertaste after being purified. Measuring 7.6 inches long, the purifier comes with a nylon case and a user’s guide. It exceeds U.S. Environmental Protection Agency guidelines for testing microbiological water purifiers.

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