Yeah, you could use a bandanna to pre-filter smut from the water. However, there is a feature on this that ROCKS. You can completely immerse a bottle with the pre-filter intact, open the little air valve, and fill quickly under water. You can also pour water into it for filtering, if you prefer to do it that way.
Quick tip, which Hydro Photon included in their directions. If you put water in it, and it doesn't seem to be filtering through, make sure to pre-wet the filter and give the surface of it a rub with your fingers to fully saturate it. Then it will start passing water.
The mesh is so fine it holds water when dry. At least I found that to be the case. This mates up perfectly with a Gatorade bottle, which is my preferred bottle. You could also do soda/water bottles with the funnel attached.
VERY LOUD. I tried it full bore inside and rang my ears. lol The dog ran and hid under the bed. :)
Super lightweight, no pea to come loose. I just bought four of them and will grab a few more for putting into 72 hour kits.
I opted to purchase the "Opti" version of the Steripen, as I've heard it's the newest version that is less problematic. It uses an optical sensor to detect the water. The older versions (aka Steripen Classic) use a couple of metallic pins checking for electric continuity. Some of the problems arose when a water source wasn't saline enough. The pins don't get continuity, the UV bulb won't light. Some report workarounds by adding some salt/Gatorade to the mix to have it work properly. Again, it's only for certain water sources, but I didn't want any fuss.
There is 1 button on the unit. 1 press treats 1 litre, and 2 button presses treats .5 litre. I have only tested at home in a glass of tap water so far. I don't know how the optical sensor works, but when I dip it in a glass of water, the UV bulb lights up and begins the process of blasting the water. You simply stir the water lightly until the light goes off and a green LED indicates the process is complete. If for some reason the LED lights up red, the process was incomplete, and you'll need to re-treat.
Semi-turbid water can be treated, but it takes two complete cycles. You have to use your own judgement as to what is turbid or not. I also purchased the pre-filter that goes over the neck of a bottle and has a 4 micron screen to keep bigger floaties out.
Negatives are that I actually have to treat a wider-neck bottle. It will not insert into a narrow-necked 'soda' or water bottle, (the Classic model does, however). A Gatorade bottle works fine -- and even mates perectly with the pre-filter. Would also work great with Nalgene bottles. The Gatorade bottles are light and durable, so that's what I'll stick with for my use. It also cannot be used to directly treat a Camelback/Platypus bladder. Rather, you'd have to treat a bottle-ful and pour into the bladder.
It uses a pair of CR123 camera batteries. The unit came with a pair of Energizer brand cells. I've ordered a 6 pack to have on hand, and will take a spare pair with me on the trails. I'll still be keeping a backup method with me, whether that be chlorine or iodine solution. I'll update as I use it in the real world, and report any concerns or findings.
I have a pair of medium and a pair of small, so I can mix and match depending on the weather. My Ledge 20 degree synthetic bag will actually stuff into the medium size. I was amazed. Small is perfect for clothes or other loose things. Winter clothes would probably go in a medium.
The welding is HEAVY DUTY. These bags are VERY well made and I have no doubts about it holding up. Everything goes in the bags, bags go into the pack, and I'm ready to roll.
I used this on an older nylon shell and made it repel water again. Last winter camp I got soaked in a heavy storm, and knew this jacket needed some help. Nikwax was the first thing I thought of.
There is plenty here in the bottle that I should be able to do it at least 3 washes and treatments. My water is EXTREMELY hard, so I have to use a bit more product (as recommended on Nikwax website).
Took outside for a test drive -- 20 degrees F out on my deck. I don't think I'd sleep on packed snow without something else, but I was fine laying on the deck. When on my side, I don't feel any spots where I'm bottoming out. It took 4 or 5 good breaths to get it to where it felt good to me straight out of the bag.
I also learned this could slide INSIDE my mummy bag if I wanted to double up a couple of these, sleeping both on one below and one in the bag. Plenty of room in the pack sack, and the free included patch kit was a welcome relief.
Grover likes that the mat matches his fur.
My boy was so excited about this new pad he wanted to test it out tonight.