I carry two of the 2L bottles, one hose, one cap. That's not UL. But I get a backup bottle, and 4L of camp water.

The reason I went with Platy is because for my group trips I take a Platypus Grav filter and when all my bottles are Platypus as well, I can ditch the Clean bag and just screw the hose onto the top of the bottles directly. When going on a trip where I'm responsible for just myself for water, the 2L Platy makes an Aqua Mira Frontier Pro filter easy to use since it too just screws onto the top. These are just a couple of my configurations, but since Platypus makes all their stuff so it will work together, there are tons of ways you can set up a water system to fit your needs.

The Platypus reservoirs are a good example of the ultralight philosophy: high performance at the lowest weight. The Camelbak bladders have the large, heavy cap/fill assembly plus the weight of the bladder material itself, and they are more expensive. The Platypus is just a basic bag with the fill and hose connection in the same fitting--- half the weight and 30% less cost for a 2 liter assembly. It parallels pack design: stripped down minimalist examples vs heavy, feature-burdened ones.

You will also find a large proportion of UL hikers using recycled drinking water bottles and not using bladders at all, carrying them in outside pockets. Some use the Platypus bottles in the same way. This was in revolt to the polycarbonate Nalgenes which are 6.2oz and $10 each, vs the drinking water bottles that are under 2oz each and nearly free. Typically using two, a hiker can drop half a pound and spend less, which is much harder to do with a down sleeping bag or shelter, where an 8oz drop might cost you hundreds.

Great point about modularity. Thank you for pointing that out Bloodworth.

I like "light" but I like smart better yet.

Platypus Hosers,Platy Bottles, etc are the best of all the liquid storage devices I have found to date. I absolutely hate the stupid design of CamelBak, Nalgene/Osprey, Sawyer, etc with the opening on the flat face of the container. There are going to be times when you need to pour from it. Try it with any one of those. Oops, precious water loss...

I have owned them all, Platys are the best IMHO. Too bad they are cutting down and going to "cool" shapes and sizes.

I think it has to do with the philosophy of the lightweight packer.

Camelbacks are systems. They have packs you place them in so you can wear them. That makes them heavy. I have seen many a hiker use their 3L Camelback full of water strapped to the outside of their pack. If you just use the bladder and place it in or on top of your pack with a hose it is still a heavy option.

Platypus are light and fold nice and small. I am like many here. I use a 1L bottle, such as a plastic WIDE mouth soda bottle that goes in a pocket on my pack. I refill as needed. The Platy stays folded up for later use. When I get to camp and I need more water, fill my soda bottle and my 1L Platy for dinner, etc.

I had one develop a small leak on the side. Patched with those little Platy patches. I am sure it was from using it around granite surfaces.

Scott

I had a new 3L Camelback and it was just over seven ounces. A 3L Platy Hoser is 3.61 ounces. Sure, it's not as easy to get water into, but it's half the weight and has not presented any major issues for me. I like the hose. I find it easier to get at than taking a bottle out of a side pocket and then trying to get it back in.

If you need water bottles, get a Gatorade or other similar bottle. They come free with some kind of liquid and are much lighter than Nalgene's or (most) other purpose-built containers. And of course the cost is right.

As Conrad noted, the only thing that is bad about the hose is that you can't monitor your remaining water without taking your pack off. Not usually a problem for me though. -The small weight penalty to carry a bladder is offset by the ease of use for me. YMMV.

In two years, I have had three Platypus hydration systems fail on me.

Although heavier, the MSR drom bags are far more durable and will accept hot drinks. The Platypus won't.

I'm surprised nobody here uses an Ortlieb bladder.
I use a 4L Ortlieb bladder that weighs 131 gram/4.6 oz. That is only slightly heavier than 2 2L Platy's.
My bladder is very durable. I've never had a problem with it while I've seen several Platypus bladders fail. My Ortlieb also functions as a very comfortable pillow.
It has a big opening which makes it easy to fill and a small opening which can be used in combination with a hose or a gravity filter.
Another advantage I think it has over Platypus bottles is that a Platy always makes the water taste differently whereas the water in my Ortlieb tastes the way it came from the spring.
The final reason I bougt my Ortlieb was the price. I don't know what the prices are in the rest of the world, but here in Europe a 4L Ortlieb costs about €20 while a 2L Platy costs abbout €15. Seeing as I often need capacity for more than 2L the Ortlieb is much cheaper.

Your comment about Platy's making the water taste differently is confusing to me. I bought the platy over the camelbak because it didn't make my water taste differently. I have bought a big zip and a collapsible bottle and never noticed anything. Does platypus make some that cause a change in taste?

Could it be the hose and not the bladder? My platy's are tasteless.

I switched to the Source water bladders have antibacterial coating when I used to use a bladder because of antibacterial coating and the US Marines used them in Iraq and Afghanistan because it's a better system then platy's.

What got me off the internal water bladder system was my brother got sick from his camelback that he used for 30 days with out washing it. It was his fault for not washing the bladder and air drying it out. BUT I HAVE QUESTION HOW MANY OF YOU TAKE THE TIME TO WASH YOUR WATTER BLADDERS?

That's why I switched to 1 liter platy plus bottle with slime guard when they came out and Platypus switched to slime guard because it easier to air dry. Platypus realize that most people don't wash their bladder water carriers. What I don't get is why Platypus have not made their internal bladder systems with the slime guard plastic.

Then Source started shipping to America their water bottle bladders I bought their 2 liter water bladder bottle version it the same diameter as 1 liter nalagen polycarb bottle and the same height as the platy plus and hold twice as much water and stand up by it's self when set on the ground. It fits in my water bottle pocket on my pack.

Source are made in Israel and just a better product than the platys and camelback water systems.IMHO
Terry

Sadly, a lot of reports of Source brand bottle failures in the field. See www.mec.ca.