Find Your Store
Home Page

Cart, contains 0 items

When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures.
Expert Help
Earn Rewards

Platypus
GravityWorks 4.0L Replacement Reservoir Kit

3.3076923076923075 out of 5 stars
13 Reviews
$78.95
Color:One Color

Size:

Quantity


GravityWorks 4.0L Replacement Reservoir Kit

You're leading a field camp this summer and the last thing you want to do is take care of a bunch of college kids with giardia. You have the GravityWorks filtration system, but could do with a bit more capacity, so you've grabbed the Platypus GravityWorks 4.0L Replacement Reservoir Kit. Your previous dirty reservoir was getting a bit grungy, so you get to start over with a brand-spanking-new bag, and now you can store an additional four liters of fresh clean waters for your thirsty undergrads. While this kit does not include the actual filter and filtration tube, these replacement reservoirs come in handy when you need additional capacity or a couple backups—just in case.


Details

  • Replacement reservoirs for Platypus GravityWorks filtration system
  • Dual-layer laminate provides food-grade, taste-free interior
  • 8 liter total capacity supplies backpacking groups with clean water
  • Disconnect fittings interchangeable with any GravityWorks system
  • Item #CAS008D
Material
plastic
Volume
4L each
Valve
quick-disconnect fitting
Dimensions
3.25 x 9.5in
Recommended Use
backpacking, hiking, travel
Manufacturer Warranty
limited

Overall Rating

3.5 based on 13 ratings

Review Summary

1 Stars - 2 reviews
2 Stars - 2 reviews
3 Stars - 2 reviews
4 Stars - 4 reviews
5 Stars - 3 reviews

What do you think about this product?

View

Selecting an option will reload the available reviews on the page
4 out of 5 stars

March 5, 2024

Great products - PLEASE SELL THE CLEAN TANKS AND CAPS!!!

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.

Conrad
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

5 out of 5 stars

January 29, 2023

Love my GW

I have used Gravity Works for years and they have never failed me. The extra weight is worth it.

J S.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

4 out of 5 stars

November 8, 2022

Difficult to dry

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.

Tim G.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

5 out of 5 stars

October 5, 2022

I recently purchased the 4l

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...?

Neil M.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

3 out of 5 stars

July 21, 2022

Seam Failure

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.

B Z.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

4 out of 5 stars

November 5, 2021

Sell the “dirty” reservoir only as an option

I love the system, but the receiving reservoir is just a waste of money and resources. I filter directly into clean Platypus water bags (1 and 2 liter). You should sell just the “dirty” reservoir with a Platypus connector below the filter on the outlet hose.

Bill P.
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

2 out of 5 stars

March 25, 2020

Expensive replacement for the simple parts of the system

I'll start out by saying that I love my 4L Gravity Works filter system. It's an effortless and easy way to provide lots of water while camping with groups. The frustration that many people have with the thick stubborn zippers seems to be necessary to be able to resist the weight of 4L of water, and I have accepted that ease will not correlate well to the necessary resistance. The dirty bag I have no problems with, other than it is tricky to clean out the hose-attachment port. The clean bag, however, is impossible to clean out due to it being completely sealed besides the single tiny little opening through which you can add or release water. This means cleaning is limited to swishing around soapy water, and no way to ventilate or dry the entire bag to prevent mold from growing. I would prefer a second bag with a large mouth opening so I could at least clean out this bag properly, which is why I would not recommend this product if you need a new clean bag (if you need a new dirty bag, I supposed it could be worth the purchase). Instead just buy the 4L water tank as this will serve the exact same purpose but be easier to clean.

Kevins
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

4 out of 5 stars

July 9, 2019

Fine product

I wanted to be able to have more water ready to filter at one time. If only the mouth was easier to open and close, and bigger to make it easier to fill. Maybe I should have tried a 4L.

a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

2 out of 5 stars

June 16, 2019

Lasted for 2 trips, failed on the third

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!

a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site

1 out of 5 stars

May 6, 2019

Lack of a cap is dumb

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?

Leigh
a Cascade Designs brand site

Originally reviewed on a Cascade Designs brand site