Platypus Big Zip EVO Review

The Platypus Big Zip EVO stands out for its durable body and faster water flow. It's easy to fill. It's one of the few bladders we'd trust on a long backpacking trip in warm weather and offers functionality for a run or day hike as well. After testing it for over a year, we have noted the closure has a hard time closing if it's not completely clean, or it's cold outside.

Performance Comparison

A look at the Platypus Big Zip that features durable and reliable construction.

Photo: Amber King

Ease of Use

The big bite valve and wider tube offer an excellent rate of water flow. This bite valve is a step up from most, utilizing a large lever lock and larger design, that fits comfortably in the mouth. Over the last months of testing, it hasn't clogged up or been hard to turn, even while ski touring with a pair of gloves on.

Flow is fast which is great for on-the-go activities like running or hiking.

Photo: Amber King

The tube clips into a quick-release halfway up the tube, which makes unclipping the tube from the bladder nice and easy. While on a climbing trip, we had our bladder stuffed deep into the back of the pack, with gear and a rope inside. To load up with water, we simply unclipped it from this point, and removed the bladder, making it easy to access. This clip-in point makes the bladder a great option for backpacking or longer trips.

The zip-top enclosure. While it's easy to use in good weather, it's becoming harder to use over time and in colder weather.

Photo: Amber King

If you don't like the clip-in point halfway up the tube, you can simply pull the hose off the bottom attachment point, remove the mid-clip-in hardware, and reattach the tube to the bottom of the bladder. We haven't found any other bladder that offers this type of clip-in versatility. We really appreciate this when we wanted a little less hose (it's very long) and wanted to reduce weight on a longer trail run.

Here are a few of the different bite valves. We found some locking mechanisms to work easier than others. We prefer the larger bite valve (bottom) which is faster to flow than others.

Photo: Amber King

Another consideration is how easy it is to load into a backpack. Given that the material is more rigid and there is a center baffle in the center, it holds its shape well, doing better than most bladders tested. As a result, it can easily be loaded into an empty backpack or running bladder. Unfortunately, it has a wide profile, making it so that it doesn't work with some narrow hydration backpack sleeves.

A look at the ziptop closure with the complementary slide top for additional protection.

Photo: Amber King

One issue of note is the zip-top closure. Like a large ziplock bag, two sides of plastic have to come together to close the bladder up. After using it for the last year or so, we've noticed this becoming more difficult. In cold weather, if there is any water on the closure, it becomes incredibly difficult to close, making it unusable. On that note, we never had a moment where we couldn't use the bladder, but for those considering it for, say a winter camping trip, we'd recommend only using it for warmer weather due to this issue. We prefer flip-top or screw-lid closures to this design.

Ease of Care

Caring for this bladder is easy. Many of the tube components completely disconnect, and the plastic used does not promote bacterial growth. While running, mountain biking, and backpacking, we've learned that this system is pretty simple to care for. The tubes all disconnect from the hardware and their attachment points, allowing you to access all the different areas for cleaning with a brush if necessary.

All components come apart for cleaning. You can take all tubes off all attachments and completely deconstruct the bite valves to rid yourself of any accidental bacterial build-up

Photo: Amber King

The bite valve can easily be taken apart and put into a cleaning solution to ensure bacterial growth does not ensue. The reservoir itself has a semi-rigid baffle in the center that prevents the two sides of the plastic from collapsing on each other when empty. This helps to promote airflow throughout the bag. The opening is hard to keep open, but we felt that simply placing a pair of tongs at the opening did a good job to help with the drying out process.

A look at the easy pouring and filling spout that can be used with one hand.

Photo: Amber King

Our only caveat with the care system is with the opening of the reservoir. The size is fairly small, not really allowing you to get a scrubbing tool inside with ease. Nor does the bag flip inside out. While we did use this bag with sugary substances that could cause bacterial growth, we were especially careful to rinse out the bag with a cleaning tablet. If bacterial growth had been encountered, we could imagine cleaning it out would be problematic in comparison to other options that can flip inside out. Aside from that, it's easy to care for, but you need to be diligent to clean it if using sugary fluids inside.

Ease of Filling

The Platypus Big Zip uses a zip-top with a slide-top enclosure to ensure that the bladder does not leak once it's filled up. The filling process is pretty simple given the opening, and it can collect water from most water sources easily.

The handle that you pinch to get a one-hand fill.

Photo: Amber King

The Big Zip now has a handle that doesn't function for traditional use. Instead of putting fingers underneath it, like a handle, you pinch both sides to keep the bladder open with just one hand. This makes filling in a sink or from a spout super easy. The zip-top isn't as versatile as other bladders constructed by HydraPak simply because it doesn't have an elongated collecting and pouring spout that allows you to collect easily from shallow, flowing sources. Trying to fill from rivers, lakes, or taps is quite simple with this new design.

The filling process is easy, especially in deep sinks. Other models are easier to fill in shallow sinks.

Photo: Amber King

Quality and Durability

If you're seeking a durable bladder that you're not afraid to throw around, we can say this is where it's at. The reservoir features welded seams with a plastic material that is thicker than any of the other hydration bladders tested. It's puncture-resistant with great hardware integrated into the design. It offers a body that is reliable for backpacking into remote places.

Weight and Packability

This is a midweight hydration bladder weighing in at 6.90 oz. It's one of the heavier options tested (splitting ounces here…), but it still feels light in your backpack. It has a wider profile that makes it a little harder to pack in narrow backpacks, but we learned that it was only super tiny running packs that the 3-L capacity did not work in.

A wide profile that isn't super complementary with narrow running packs. While we could still fit it in, its best for wider backpacks.

Photo: Amber King

Value

Given the great durability of the bag itself and some of its simpler components, we think it is of good value. The only caveat to the design is the closure that struggles in cold weather. For every other use, it's one of our favorite and remains a high scorer and of high value because of its design perks.

Day hiking, running with a wider profile pack. This bladder is versatile, durable, and reliable.

Photo: Amber King

Conclusion