10857 10857 10857

Big Zip™ EVO - 3 Liter

Big Zip™ EVO

Premium taste-free hydration reservoir with 50% faster flow rate.
Learn More
$49.95
or 4 payments of $12.49 by Afterpay
1.5 liter
2 liter
2 liter (Lumbar)
3 liter
  • In Stock
Find Online
Introducing the Big Zip™ EVO—the latest evolution in taste-free hydration. The Big Zip EVO delivers a significantly higher flow rate than previous Platypus reservoirs and a host of new features, making it a great option for backpackers, hikers, and mountain bikers. Available in 1.5L, 2.0L, 3.0L and a Lumbar 2.0L.
  • Secure SlideLock: Slides both directions to easily open, securely close and fill reservoir.
  • Handy Pincher Grip: Allows for easy one-handed filling.
  • High Mount Quick-disconnect: Offers fast, easy access—no more digging down in your pack.
  • Leak-proof Shut-off Valve: Instantly stops flow and offers reliable stowing.
  • Semi-rigid Center Baffle: Offers low-profile support and makes for easy cleaning and drying.
  • HyFLO Self-sealing Bite Valve: Improves flow along with new, larger 5/16" drink tube.
  • Funk-free: Embedded Silver-ion protects clean water from mold & bacteria.
  • Pure Platy Experience: All materials are certified taste-free, BPA-free, BPS-free, and phthalate-free.
Outdoor Gear Labs | Editors Choice 2020
  1.5 liter 2 liter 2 liter (Lumbar) 3 liter
SKU 10859 10858 10860 10857
Capacity (Standard) 50 fl. oz 70 fl. oz 70 fl. oz 100 fl. oz
Capacity (Metric) 1.5 liters 2.0 liters 2.0 liters 3.0 liters
Weight (Standard) 5.6 oz 6.0 oz 5.4 oz 6.5 oz
Weight (Metric) 0.16 kg 0.17 kg 0.15 kg 0.18 kg
Width (Standard) 8.5 in 8.7 in 14 in 9.0 in
Width (Metric) 21.6 cm 22.1 cm 35.6 cm 22.9 cm
Length (Standard) 13.0 in 15.0 in 8.7 in 17.2 in
Length (Metric) 33.0 cm 38.1 cm 22.1 cm 43.7 cm
Film Polyurethane / Polyethylene Polyurethane / Polyethylene Polyurethane / Polyethylene Polyurethane / Polyethylene
Bite valve material Silicone Silicone Silicone Silicone
Country of Origin Made in the U.S.A. of U.S. and Imported Materials Made in the U.S.A. of U.S. and Imported Materials Made in the U.S.A. of U.S. and Imported Materials Made in the U.S.A. of U.S. and Imported Materials
Do any of your products contain BPA, BPS, phthalates, or use polycarbonate?
No. All Platypus hydration products are 100% BPA-, BPS- and phthalate-free, and do not use polycarbonate.
How do I clean my hydration system?

Hand wash your hydration system using warm or hot soapy water. Using our Cleaning Kit helps access tough to reach places.

For deeper cleaning:

  • a. Per liter volume of your hydration system, add ¼ Cup of baking soda to ¾ Cup of water and shake for 30 seconds (e.g., for a 2L hydration system use ½ Cup of baking soda with 1 ½ Cup water).
  • b. Add ¼ Cup lemon juice per liter, close and shake 10 seconds, then vent by opening hydration system away from face.
  • c. Re-seal hydration system and repeat shaking and venting three times. Expel as much air as possible, close hydration system, and soak for 20 minutes.
  • d. Dump solution and rinse hydration system three times with hot water.

Caution: When adding lemon juice to baking soda, effervescence occurs and will cause pressure to build in a closed Platypus product.

How do I dry my hydration reservoir?

In general, it is optimal to prop or hang hydration system reservoirs upright to dry—this allows moisture to evaporate and escape upward.

Drying Big Zip™ reservoirs is easy. First, wipe interior with a dry towel (made easy thanks to the large opening!). Then prop the reservoir open with the SlideLock™ slider and let it all air dry.

Another great way to dry a hydration system is with a plastic bag dryer, widely available at kitchen supply stores and numerous online retailers.

Is it okay to freeze my hydration reservoir with water in it?

Yes. To do this, add water to your reservoir, being careful to not over-fill (fill no more than ¾ full—water expands as it freezes; it can burst your reservoir if you over-fill it). Purge all air and then lay your reservoir flat in the freezer overnight. Remove and enjoy a steady source of cold, refreshing hydration as the water melts!

Also, did you know that you can occasionally skip cleaning your reservoir by storing it in the freezer? It’s as simple as rinsing the whole system with fresh water, then placing it in the freezer until the next use.

How do I disinfect my Platypus hydration reservoir?

To disinfect your Platypus hydration system, fill it with a solution of unscented household bleach and water, using a concentration of 2-5 drops per liter of water. Close and swirl for 10 seconds. Squeeze the bite valve to flush the hose and valve, being careful to keep the valve opening over the sink. Leave filled overnight. Dump solution and rinse hydration system (including hose and bite valve) three times with hot water, then air dry.

Note: for an eco-friendlier option, use a chlorine-free, hydrogen peroxide-based bleach alternative.

My new bite valve doesn’t seem to be working. How do I get the water to flow?

Does your hydration system have a shutoff valve? If so, it may be closed. Open it by twisting the bite valve 90 degrees (Clockwise closes it, Counter-clockwise opens it).

If that doesn’t work, you may be biting the valve too hard. The Platy HyperFlow Bite Valve is designed so that you don’t need to bite very hard. If you bite too hard the flow will be completely cut off. With your teeth, compress the valve lightly (only 30% to 50%) and water should flow.

My bite valve comes off easily. What should I do?

If your bite valve is coming off easily, we recommend re-fitting it by following these steps:

  • a. Remove the bite valve from the drink tube.
  • b. Cut a small section off the end of the drink tube.
  • c. Clean the bite valve and hose with rubbing alcohol.
  • d. Wet the end of the drinking tube with water or saliva and slide the bite valve back onto the end of the drink tube.
  • e. Let it all dry (at least overnight).

This should result in an excellent connection between the bite valve and drink tube, and the bite valve should stay in place.

How do I prevent the water in my hydration reservoir from freezing in cold weather?

To help keep drink tubes and bite valves from freezing up, sip often to maintain flow, then blow any residual water back into the reservoir after you’ve finished drinking. It helps to squeeze the bite valve momentarily to remove any last drops. Using our Bite Valve & Drink Tube Insulator deters freezing, too.

Also, even if you are using the Bite Valve & Drink Tube Insulator, it still helps to keep as much of the drinking tube covered as possible, such as routing it inside a pack, strap, or jacket. You can also start off the day with warm or hot water in the reservoir, packing any extra clothing layers around it.

Is there a way to filter water directly into my reservoir without removing it from my pack?

Yes. Simply remove the bite valve on your hydration system and connect the end of the hose directly to your filtration system’s outflow port.

Our GravityWorks™ filters are available with direct-to-reservoir and direct-to-bottle adapters for optimum versatility. Connecting a GravityWorks filter to your reservoir creates what is arguably the lightest, most compact and efficient way to get filtered water.

The zipper tracks on my Big Zip™ reservoir are hard to close. Can I make it easier?
Yes. Periodically adding a little Vaseline to the tracks will keep them supple and easy to close. Wipe away any excess Vaseline. In the field, a little lip balm or water can do the trick.
My water sloshes around in my reservoir. Can I make it stop?
Absolutely. After filling your reservoir, simply turn it upside down and simultaneously squeeze both the reservoir and the bite valve until all excess air is purged. You can also invert the reservoir and suck out the excess air, if you prefer. Either way—bye, bye sloshing!
Can I get small replacement parts for my hydration reservoir?

Many replacement parts can be purchased directly from us online on our Accessories page or from one our retailers. If you cannot find what you’re looking for, our friendly customer service team can assist you:

For customers outside North America, please consult our International Distributor listings.

Free Shipping on Orders over $50

We offer complimentary FedEx Ground shipping for US orders over $50. Learn More

Orders Shipped in 1-2 Days

We do our best to get all orders out within one business day, Monday through Friday. Learn More

No Hassle Returns

We accept returns within 30 days of purchase. All returned items must be in new condition. Please be sure no dirt, grass or pet hair is on the item you are returning. Learn More

We Believe in What We Build

At Platypus, we take pride in engineering the highest-quality outdoor gear available, and we stand behind everything we make. Platypus gear is built to be exceptionally durable. And we back it up with the best service in the industry, all to keep your gear performing for you—and out of landfills. Visit our Platypus Warranty page for more info.

Portrait of our repair shop crew

Reviews