TLDR: The Platypus Big ZIP EVO 3L Bladder is a well constructed bladder with a thoughtful design that will suit those looking to adventure away from water sources.

Quality & Design

I was very impressed when I first took the Platypus EVO out of its packaging. It comes across as extremely well built and you can feel the weight of the plastic is more durable than some of the other bladders out there. The sturdiness doesn’t stop there, Platypus chose to use a larger than standard 5/16″ hose and increased the wall thickness. This should help increase resistance to kinks, tears and punctures as well as offer an increased flow.

One thing I like is you don’t get a plastic taste like with other bladders. Even before washing the bladder I couldn’t detect any hint of plastic. This doesn’t matter that much to me. I am used to using a vinegar solution to thoroughly clean and remove any residual taste in my bladders. For those that are sensitive to that plastic taste, rest assured you won’t taste anything other than your water.

Ease of Use

With the upgraded 5/16″ tubing and the larger bite valve, the EVO is significantly easier to consume water with a solid flow. I found that when in my pack and with pressure from the other gear surrounding the bladder, all I needed to do was open the bite valve and the water would start flowing immediately. It wasn’t until I got down to about 1L that I had to start sucking on the valve to get the water out.

The bite valve itself is well designed. It’s comfortable in your mouth and the valve lever is easy to open and close. The bite portion of the valve is a bit on the sticky side so if you happen to set your bag down and the valve hits the dirt you may be spending a bit of time cleaning the dirt off.

As far as filling goes, you really couldn’t ask for a simpler fill system. The EVO fills from the top by removing the sliding bag lock and separating the ziploc seal. Platypus incorporated a “pinch to fill” mechanism that makes it easy to hold open the mouth of the bladder while filling from a sink or submerging under water.

Care & Storage

The EVO is really no different from any other hydration bladder. When it comes to cleaning and storage before next use you have a few options. Platypus recommends hand-washing with hot soapy water and hanging it upright to dry. Personally, I like to hand-wash the pack and then store it in the freezer until my next trip.

Weight & Size

The total weight of the EVO with the hose sits around 8.8oz. It’s certainly not winning you any points in the ultralight category. However, the extra ounces really add to the rigidity and quality of the bladder. In terms of dimensions the EVO measures at 17.2″ tall and 9″ wide. This is noticeably larger compared to other 3L bladders. I would recommend measuring your pack before purchasing to ensure a good fit. I have had no issues while using it in both my Osprey Exos 48 as well as my Osprey Atmos 65.


As of this post you can pickup the Platypus Big Zip EVO 3L on Amazon for $39.99. For me, the pros out weigh the cons and despite a higher price over some other cheaper 3L bladders, it delivers on value and performance.

Sawyer Fast Fill Hack

If you’re like me and you don’t like taking your bladder out of your pack every time you want to fill up, you’ll certainly want to look at some adapters to connect a filter. Unfortunately, what you’ll quickly discover is due to the larger tubing diameter, most common fast fill adapters and fittings only fit the more common 1/4″ tubing. So here’s what I did to allow me to connect my Sawyer Squeeze.

Platypus Big Zip EVO 3L Bladder Review & Sawyer Fast Fill Hack

First, you’ll need a Sawyer Squeeze. I recommend the full Sawyer Squeeze Filtration System as it has everything you need and more.

Second, you’ll need to pick up a spare Platypus Big Zip EVO drink tube. Make sure that you order the correct tube for your bladder. Each size bladder has a slightly different drinking tube. We just need the quick connectors from the spare tube which are the appropriate size for the 5/16″ diameter tubing. Unfortunately as of right now, Platypus does not sell standalone connectors.

Third, grab Sawyer’s Fast Fill Adapter Kit. The kit comes with a 1/4″ hose with male adapter and a screw on connector that screws right into the outlet of your Sawyer Squeeze.

Finally, we start the assembly process. Cut your drink hose using scissors, wherever you want your quick connect to be. Remove the female quick connector from the spare hose. Push the hose you just cut onto the connector, make sure you get a good tight seal here.

Next, grab the male connector from the spare hose and push it on to the bite valve hose. Now you can start to see how the system functions. When you’re not filtering water to fill your bladder the bite valve connects to your drink tube with the new quick connector we added inline. When you need to fill your bladder all you need to do is disconnect the bite valve and connect the fast fill tube and use your Sawyer Squeeze just like you normally would.

If you have any other thoughts or experiences please feel free to comment below!

Leave a Reply

Your email address will not be published. Required fields are marked *