Name: John R. Waters
Age: 57
Gender: Male
Height: 5 ft 9 in (1.7 m)
Weight: 178 lb (81 kg)
Email Address: exec at bysky dot com
City, State, Country: White Lake, Michigan USA

Backpacking Background

My backpacking began in 1999. I've hiked rainforests in Hawaii, Costa Rica, and Puerto Rico, on glaciers in New Zealand and Iceland, 14ers in Colorado and Death Valley's deserts. I hike or snowshoe 6-8 miles (10 km-13 km) 2-3 times weekly in Pontiac Lake Recreation Area, with other day-long hikes on various SE Michigan trails. I also hike in Colorado and am relocating there, which will increase my hiking time and trail variety tremendously.

My daypack is 18 lb (8 kg); overnights' weigh over 25 lb (11 kg). I'm aiming to reduce my weight load by 40% or more.

Product Information and Picture (from manufacturer's website)
http://www.watchfuleyedesigns.com

Manufacturer: Watchful Eye Designs
Style: O.P. Sak
Colors: Clear
Sizes and MSRP:

O.P.SAK NEW 9 X 10 3-PACK	$7.79
O.P.SAK NEW 12.5 X 20 3-PACK	$10.59
O.P.SAK NEW 28 X 20 2-PACK	$13.29

Features: New durable O.P.SAK 100% odor barrier bag. No gusset. Store food undetected at the camp site. OK to add boiling water to the O.P.SAK to prepare food as the film is FDA approved. You can not place the O.P.SAK in boiling water. The O.P.SAK uses the same seal as the ALOKSAK and offers all of the same air and water proof features. If you need a storage and transport bag that is tolerant to extreme heat, the O.P.SAK is the bag for you.

Product Information (from tester)

Color: Clear
Size:

Features:
For an in depth description of the O.P. Sak, please refer to my Initial Report.

Field Conditions/Completed Test Results

I used these bags over the course of several weeks; camping, hiking and traveling on airlines, in my backpack, my carry-on and in checked luggage.

Since I had different sizes, I used them for a variety of content material and even used a bag in an outdoor test for four days in hot sunlight exposed to the elements on the ground next to a grocery store resealable bag for comparison (see pictures).

The outdoor test involved using a regular store-brand "freezer-type" resealable bag and the 9 in x 10 in (22.9 cm x 25.4 cm) O.P. Sak. Nothing is much more fragrant when warmed in the sun than extra buttery microwaveable popcorn packs, so I placed one in each bag. The bags were then placed on the ground in a desolate location in southern Colorado where I could monitor them during the week. The O.P. Sak showed no signs of moisture entering the bag or any signs of bugs. Neither attracted any other animals as well, even though there is plenty of wildlife at this location. It was interesting that when I opened the O.P. Sak at the end of the test, there was a rush of moisture into the bag and the popcorn did get wet. I left the popcorn pack inside the O.P. Sak and carried it around as I traveled for about 6 weeks. The oil from the popcorn pack did stain the O.P. Sak and I was not able to remove the oil from the inside of the Sak. I used dishwashing soap, soaking it for a few days, but this O.P. Sak itself is now not useable for any other foodstuff since it retained the popcorn butter smell inside and is coated with the oily film.

	After five hot sunny days at 95 F (35 C) with changes to cool 45 F (7 C) evenings, the regular grocery store resealable bag was infiltrated by ants and condensation and the popcorn bag started to show signs of butter inside the bag due to the moisture.
	In fact the ants ate their way into the regular grocery store resealable bag and the bag started to fill up with water from evening thunderstorms. So when I held the bag up, the corner leaked water. The popcorn pack was not at all useable. A regular grocery store resealable bag was no match for the O.P. Sak in this test.
	The O.P. Sak, although covered with mud and rainwater, was completely dry on the inside and the popcorn pack was completely useable.

I used another O.P Sak to hold ground coffee. Loose ground coffee. This was a new Sak the same size as the one I used for the popcorn pack. Again, this was taken hiking, overnight, into the desert, on airplanes, into motels, checked luggage and carry-on. It never broke its seal and it kept the coffee fresh and dry for 6 weeks. However, I think this bag will not be useable for other foodstuffs either. I think it would be exceptionally time-consuming to clean this out and get rid of the coffee odor and to remove the fine coffee dust that is clinging to the side of the bag. So when the O.P Sak is designated "reusable", it appears that the items placed in the bag need to be in their own containers, or that the contents be the same for each use.

"Patented Leakproof/Airtight SEAL" is what the label says on the O.P. Sak.; "tested and approved by the Navy Experimental Unit" and I can see, after testing these, that they will keep dry stuff dry under extreme conditions. However, my tests with liquid INSIDE the bag did not go well. Yes, when I blew them up like a balloon I could pop them open and, yes, when I filled one up with water and pushed down real hard it also popped open and sprayed water all over. Actually they will pop open with water in them without a whole lot of pressure. I found that out by filling a bag 1/2 full with water and placing in my backpack. Fortunately, just in case, I also encased the bag inside a garbage bag, so it leaked into the garbage bag and not my pack. Had that been human waste or other gooey material my bag would have been rather messy. The seals seem very lightweight and not rugged enough to handle say a drop to the ground or a fall on my pack that may crush the O.P. Sak inside my bag. I also discovered that once the seal is broken and leaks liquid, the seal becomes less effective. I would need to dry the entire seal to get it to be as effective as when I first used the bag and that is quite a task to do quickly.

Just as an experiment, I obtained a BioHazard bag from the local hospital. Other than the fact that it has a red BioHazard label on it, it looks just like a grocery store resealable bag and isn't even as heavy as the new freezer bags being sold today. I don't know what they do that is different with these bags, but I filled the bag with tap water and turned it upside down so the zippered top was down and pushed it into the side of the bathtub as hard as I could. Really hard and it would not open. I took both hands and squeezed and not a leak. I did all but step on it and it would not leak or open.

Now I tried the same thing with the O.P. Sak. Filled it half full with water, and rubbed it against the side of the tub in a circular motion to try and simulate moving around in a backpack. The seal broke within a minute. It was a gentle break, not a pop that squirted water all over, so it would have been a "gentle leak" but it did not take long to get water to come out of the O.P. Sak.

Just for kicks, I also filled up a cheap freezer bag half way with water and did the same thing and it popped open in 10 seconds spraying water all over the place.

Summary

These are great bags to use for dry foodstuffs and fragrant material. I would have no issues with putting dry food in these and being assured that a bear would not smell a thing. Of course, like always, if the smell gets on my backpack when I'm getting material out of the O.P. Sak that's a different story. If I transfer the smell to the outside of the Sak there is nothing I can do to mask the smell. I was very impressed with how well it kept things dry. They are very waterproof and do not allow water IN. I would not use these for storing liquids of any kind and would only use them for human waste if I were to encase it in another container, perhaps a second O.P. Sak, because although they don't allow the odor out, they do not contain liquids inside the Sak from leaking out as well as I would want a bag to.

Continuing Test Plan

Over the next few months I will use these Saks extensively to hold foodstuffs and I will even try to store some less than liquid material, such as peanut butter. The Sak filled with coffee will continue to be transported and reported on. These Saks will be getting quite a workout during an extensive travel and hiking schedule. I am interested in seeing how they wear now, since I am seeing signs of creases and folds, none of which affect the performance yet, but these additional tests will stress them out even more.

I will also report any other issues that arise during the testing period.

Thank you for the opportunity to test this product!

John R. Waters

Read more reviews of Watchful Eye Designs gear
Read more gear reviews by John Waters

Field Report

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