Platypus  GravityWorks Replacement Reservoir Kit - 4 Liter

Hands down the best water filter I’ve ever used in 30 years of drinking from backcountry streams and lakes. It’s miraculously easy to set up, walk away and the next time you glance at it you have four liters of clean, clear, and tasteless water. My only gripe is why can’t the Clean reservoir have the same wide zip-loc opening as the Dirty reservoir to allow easier drying and cleaning? The little soda cap opening on the Clean reservoir doesn’t allow enough air exchange to permit proper drying in less than 2 days, promoting mildew growth and more frequent cleaning, which is also a pain because of the small opening. So close to five stars, but not quite.

Great product but the dirty bag doesn't come with the quick disconnect elbow and the clean bag doesn't come with the blue screw on cap or the blue elbow....they are pictured with them but doesn't come with them. I called Platypus and ordered those items and Steve sent them to me for free after some discussion. 1- 800-245-2992

Great system but there is evidently some product quality issues that make it through as noted with some of these reviews. For me, the Clean bag has delaminated along one side of the hard threaded plastic. This results in water spraying everywhere when filling directly from the Clean bag, or newly filtered water leaking out of the Clean bag if it is being filled from the filter line at certain angles. Also as noted by others, I hear nothing back from the Cascade Designs warranty team after filling out about one form per year. I wouldn't complain about purchasing it a new bag if it were more reasonably priced.

I love my Platy system, but lost my clean reservoir bag. This kit sounded like the perfect solution, rather than buying a new system. Opened the bag, and no cap. Well, sure enough, a cap is not in the description, though the bag in the picture is apparently holding water, so that felt a little misleading. Still love Platypus; works awesome! Just be aware that this won't come with a cap for the 'clean' reservoir; the 'dirty' reservoir does have the quick disconnect female connection.

I bought this system back in 2014 and have used it since. It is great for our needs. When we hike, we generally can go through a bunch of water. The gravity system filters fast and let's you scoop a bag of dirty water, and then go do something else while it filters. Back flushing quickly cleans the filter (though I bought a spare filter, I haven't needed it yet. Highly recomended!

I love this system! I was looking for a different way to filter water which would allow me to go and complete other camp chores. Since I already had several Sawyer mini filters I decided to order this as well as a hose replacement kit. This seems to work pretty well. I like the Sawyer filters but am not a fan of their gravity system. I like the Platypus bags but feel that their filters are a bit higher priced.

I recently purchased the 4l replacement reservoirs for my Platypus filter which had the 2l reservoirs. I used them on a backcountry hunt/camp. Unfortunately no pictures. They were a game changer. I love the ease of using the Platy system and the 4l size was great. Allowed us to fill our water bottles, make food, and some left over for hydration before having to make our way to the stream to refill. Odd that the clean res. didn't come with a cap though...?

I backpack for at least one week per summer. After two trips, the dirty reservoir valve jammed and I couldn't clip the filter to it. I never let this part of the bag touch the ground it simply clogged with the silty water I was having to filter. I ended up having to filter water through my sock and ad iodine tablets for the last two days of hiking. I like the convenience of this system, but bring a back up of iodine tablets in case!

Awesome system!!! The clean bags double as really great longer distance water containers (IE kayaking for a few days with no fresh water available..) can you pretty please sell them in 4L and 6L with caps??? Much more trustworthy than the "Platy bag" with the seal along its length. You might even make the bags so the caps attach with a tether, they're very easily to lose in the field.

Why in the world would you sell a reservoir to hold water without a cap? Filter the water into the clean reservoir and then disconnect so that it can spill out everywhere? I thought for sure my purchase had not been packaged correctly. I understand that other caps are compatible, but why not just sell it with one?