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CrazyCap 17oz Review

A UV bottle cap purifier that removes viruses from water sources
crazycap 17oz backpacking water filter review
Credit: CrazyCap
Top Pick Award
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Price:  $79 List | $79.00 at Amazon
Pros:  Lightweight construction, purifies water with a touch of a button, waterproof, fast charging, long charge retention
Cons:  Can't filter particulates, doesn't adapt to many other bottles, small bottle size
Manufacturer:   CrazyCap
By Amber King  ⋅  Apr 23, 2020
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  • Water Quality - 20% 5.0
  • Durability & Maintenance - 20% 7.0
  • Treatment Time - 15% 5.0
  • Weight & Packability - 15% 4.0
  • Ease of Set-Up - 15% 9.0
  • Ease of Filtration - 15% 10.0

Our Verdict

The Crazy Cap is a virus and bacteria-killing water bottle cap that purifies with the touch of a button. It stands out because of its lightweight construction that you can take anywhere. It's not bulky, making it a wonderful traveling friend. It utilizes UV-light that dismantles the DNA of disease-causing contaminants. The bottle and cap are both incredibly durable, insulated, sealed, and waterproof. Not only does it purify water in 60 seconds with a simple touch of the button, but the light can be used to clean surfaces that might also be contaminated. Plus, it can't be accidentally turned on, as it needs your finger to do so. It stands out as our Top Pick because of its ease of carrying, use, and long charge that'll last for at least a week. Enjoy its benefits and clean water wherever a contaminated, clear water source might be.

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crazycap 17oz backpacking water filter review
This Product
CrazyCap 17oz
Awards Top Pick Award Editors' Choice Award Top Pick Award Best Buy Award 
Price $79 List
$79.00 at Amazon
$29.08 at Amazon
Compare at 2 sellers
$38 List
$37.95 at REI
$15.00 List
$14.95 at REI
Overall Score Sort Icon
Bottom Line A UV bottle cap purifier that removes viruses from water sourcesSimple filtration that is lightweight and reliable for individual useThis filter is an excellent choice for lightweight and durable collapsible bottle filtrationThese drops are a reliable and lightweight option to carry all over the world
Rating Categories CrazyCap 17oz Sawyer Squeeze LifeStraw Peak Squeeze Aquamira Treatment...
Water Quality (20%)
Durability & Maintenance (20%)
Treatment Time (15%)
Weight & Packability (15%)
Ease of Set-Up (15%)
Ease of Filtration (15%)
Specs CrazyCap 17oz Sawyer Squeeze LifeStraw Peak Squeeze Aquamira Treatment...
Type of Filter/Purifier UV treatment Squeeze, in-line, on-the-go Squeeze Chemical treatment
Measured Weight (entire kit) 12.6 oz 5.7 oz 3.8 oz 3.0 oz
Number of Liters (L)/Gallons (gal) per Lifetime 236,588 L / 62,500 gal 378,541 L / 100,000 gal 2000 L / 500 gal 114 L / 30 gal per package
Filter Media or Active Ingredient UV light Hollow fiber Hollow-core membrane microfilter Chlorine dioxide
Effective Against Bacteria? Yes Yes Yes Yes
Effective Against Protozoa? (Giardia,Cryptosporidium) Yes Yes Yes Yes
Effective Against Viruses? Yes No No Yes
Effective Against Chemicals? No No No No
Effective Against Heavy Metals? No No No No
Removes Particulates (sediment, microplastics)? No Yes Yes No
Filter Pore Size N/A 0.1 micron 0.2 microns N/A
Advertised Flow Rate N/A 1.7 L / min 3 L / min N/A
Dimensions N/A 11 x 6 in 9.48 in x 4.8in x 2.67in N/A
Storage Capacity (L) 0.5 L 2 L 1 L N/A

Our Analysis and Test Results

The Crazy Cap is our favorite UV light system. It's our favorite because of its lightweight design that's easy to carry anywhere you go. We also love that you can purify water while simply touching the lid, and walking away. No hands needed to swirl or press for purification. It has a long battery life that'll last at least a week after a charge, and it's incredibly durable. If you're planning on traveling internationally or already live in a place where waterborne viruses are a problem in municipal water, this is a wonderful, easy product.

Performance Comparison

crazycap 17oz backpacking water filter review - the crazycap bottle is insulated and will purify water with the...
The CrazyCap bottle is insulated and will purify water with the touch of a button. It's our favorite UV bottle purifier system.
Credit: Amber King

Water Quality

This UV filter is a purification system that uses a 278nm wavelength to destroy bacteria, protozoa, and particulates.

This wavelength, when in contact with microorganisms, scrambles their DNA, not allowing them to reproduce. It offers two modes. The first lasts for 60 seconds, which kills about 99.1% of contaminants, while the crazy mode (90 seconds) kills 99.99999%. This is not a filtration system, so don't expect it to rid the water of particulates, chemicals, or pesticides. It's a great system for front country use or while in the backcountry. If you're in murky water sources, use a handkerchief to filter out larger particulates.

crazycap 17oz backpacking water filter review - the uv light is in the cap and will purify clear water sources in a...
The UV light is in the cap and will purify clear water sources in a touch.
Credit: Amber King

Durability & Maintenance

There isn't much to this system. We used this bottle over the course of 1.5 months, using it every day. We love how durable the bottle is and how easy it is to maintain. Just don't lose the charging cord!

On average, we would use the "normal" mode three times per day. Through this time, we had to charge it once every two weeks. If you do the math, you're looking at about 60 filter cycles of 17oz of water before needing to recharge it. Charging is easy. Simply plug it into a USB port, and wait for about 1.5 - 2 hours. You can also use this trick on the trail if you have a solar-powered battery pack, but expect charging times to vary based on the system you have. To clean it, simply empty the bottle, and put it on crazy mode (90 seconds) and the bottle will be sterilized.

crazycap 17oz backpacking water filter review - performing some drop tests. the bottle remains without dents and...
Performing some drop tests. The bottle remains without dents and only a few scratches after being thrown around on rocks.
Credit: Amber King

The bottle that comes with the set also seems to be quite durable. We've taken it skiing, hiking, and used it while working from home. It's also been thrown around quite a bit in the car. After all this, the color is still intact with just a few scratches from accidental big drops. The bottle itself hasn't deformed, even after accidentally dropping it on a pile of rocks, completely full.

crazycap 17oz backpacking water filter review - the lid is completely waterproof as well. so don't worry if it gets...
The lid is completely waterproof as well. So don't worry if it gets wet!
Credit: Amber King

While we didn't have any issues with the Crazy Cap, we must speak to some of the online reviews we've read. While negative reviews are few and far between, a few people mentioned that their crazy cap didn't work after two months of use. Others, however, heralded it for great performance after they traveled to exotic locations for 2+ weeks, such as Africa and Mexico, where water-borne viruses are a concern. Overall, our experiences show this to be quite an awesome at-home and exploration device. Use it anywhere with fewer charges and huge battery life!

Treatment Time

The bottle that comes attaches can treat 17 oz of water, which is about 0.5 liters. If you wanted to store more water, you could easily get a larger, compatible bottle, or simply bring a collapsible bottle with you. This means it would take about 2 minutes to purify 1 liter of water.

If you wanted to purify it to remove the most contaminants, you're looking at about three minutes for one full liter. While this isn't the fastest time out there, it earns a higher score because treatment is completely hands-free and easy.

crazycap 17oz backpacking water filter review - treatment is simple. just touch the top two times for normal mode...
Treatment is simple. Just touch the top two times for normal mode and wait 60 seconds - hands-free!
Credit: Amber King

Weight & Packability

The bottle and filter weigh 12.6 oz, with the top weighing just 3.15 oz (with the charger).

crazycap 17oz backpacking water filter review - it fits nicely into the pockets of most backpacks.
It fits nicely into the pockets of most backpacks.
Credit: Amber King

Our testers are fans of collapsible bottle storage systems, so this isn't the item we'd use for a backpacking trip (plus, what happens if the battery shorts?!) but its one we'd definitely bring along if we're traveling and purifying filter water from sinks or taps. The bottle itself is light enough to hike with. Plus, it insulates really well, keeping warm beverages warm, and cold ones, cold. We tested this out by putting tea into the bottle. It stayed warm for over 8 hours but slowly decreased in temperature during that time. Still, impressive insulation.

crazycap 17oz backpacking water filter review - it's not the lightest water bottle out there, but it does the trick...
It's not the lightest water bottle out there, but it does the trick for carrying around town, travelling, and hiking.
Credit: Amber King

Ease of Set-Up

Super simple. Collect the water you need and hit the button. No need to pump, squeeze, push. Everything is hands-free, so treatment time isn't a bother in the least, unlike other UV systems and bottle purifiers.

The shorter design actually fits well under most sinks and it can scoop up water from deeper sources with ease. It's also a great companion while out on a fishing or any type of boat-based trip (it has an IPX7 waterproof rating). The downside is you need to be able to reach the water source to collect from it. Make sure you collect from the top of the water column to avoid particulates, as this bottle can't filter those out. Or bring a handkerchief along as a prefilter (with an extra bottle) if you know you're going to come in contact with them.

crazycap 17oz backpacking water filter review - water collection is pretty simple. just plunge and fill.
Water collection is pretty simple. Just plunge and fill.
Credit: Amber King

Ease of Filtration

Hit the button twice for "normal mode", and fives times for "crazy mode". To check battery life, hit the top one time. After you've hit the button, all you have to do is sit back and wait. You can even collect water, hit the button, put it back in your pack, while you continue hiking. Super simple and one of the only products that'll allow you to filter on the move.

The cap will tell you what you need to know using a color scheme. For example, it if glows red, you know it needs a charge. You know the bottle is working when the cap glows blue. When it stops glowing, the process is over. To check if this actually was working, we took the top off and looked at the light. Since UV light is hard to see, we took it into a dark room and shone it on a piece of white paper. Then, you can actually see the UV light is intense. Overall, this is one of the easiest systems to set up and use, and the only hands-free system that'll allow you to filter on the go. When you're ready to recharge, attach the lid charger, plug it into a USB port, and wait for 1.5-2hours (depending on your power source).

crazycap 17oz backpacking water filter review - easily recharge from any usb outlet. it takes only a couple of hours.
Easily recharge from any USB outlet. It takes only a couple of hours.
Credit: Amber King


This UV purifier offers some of the best value on the market. If the lid stops working (or the bulb burns out) you can buy a new one quite easily. However, the bulb is said to have a lifespan of 236,588 liters, which equates to 62,500 gallons. Obviously we didn't get to test that many liters yet, but if it's true, the cost of 100 liters is just about three pennies, which equates to amazing value. Assuming that the lid doesn't kick the bucket before its alleged longevity, we definitely have a winner here. Another reason this model is our favorite UV purifier.

crazycap 17oz backpacking water filter review - take a drink, wherever you are. traveling to exotic places, in the...
Take a drink, wherever you are. Traveling to exotic places, in the backcountry, or in your office. The CrazyCap is our favorite UV bottle purifier.
Credit: Amber King


The Crazy Cap is an exceptional UV purifier that's won our hearts and an award for its unbelievable performance. At the touch of a button, you can make clear, disease and virus-ridden water into clean and drinkable agua. This is not a filtration unit, so it won't get rid of particulates. But it's at home on a hiking trail, while traveling, or at home. The UV light can also purify surfaces that you touch (like computer keys) at the touch of a button. A necessity when trying to stay clean and safe.

Amber King

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