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DayCap™ In-Bottle Filter


DayCap™ In-Bottle Filter

Transforms your favorite wide-mouth bottle into a fast and easy water filter.
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You’ve already got the water bottle, now you just need the clean water. The DayCap In-Bottle Filter seamlessly fits onto three popular wide-mouth water bottles—Nalgene®, Hydro Flask®, and Yeti® Yonder™—and transforms them into fast, safe and incredibly easy water filters. The removable filter utilizes the same hollow fiber technology as our award-winning backpacking filter systems to filter water safely and quickly. By only lightly pulling water through the spout, the speed of the filter allows you to drink as you normally would from your bottle. If the flow begins to slow down, simply shake your bottle with the DayCap and filter attached to clean it and restore the flow rate. Made of premium materials, the cap is durable, and features a sturdy loop for secure hanging and carrying. The spout is shaped to optimize flow and provide a natural drink experience. It has a flip-up leak-free cover that stays out of the way when you’re drinking. In cap-only mode, the DayCap works as a perfect everyday cap for your bottle when you’re not on the trail. With the filter on, whether it’s a day hike or a backpacking trip, the DayCap In-Bottle Filter makes worry-free hydration as easy as scooping and drinking.
  • Easy-to-Use: The drink experience is practically the same as without the filter thanks to the high-speed filter and the flow-optimized spout.
  • Proven Filtration: Hollow fiber filtration media is the same technology as our most popular and field-proven filters, with a flow rate up to 1 liter per minute.
  • Safe & Effective: Each filter is individually tested to ensure it meets all EPA & NSF guidelines for the removal of 99.9999% of bacteria and 99.9% of protozoa.*
  • Easy Cleaning: Simply shake to clean with it attached to your bottle to break up particulates and restore flow rates.
  • Optimized Design: Filter detaches with an easy half turn for cap-only mode while the semi-flexible carry loop is a sturdy attachment point.
  • Premium Materials: TPE mold construction is durable, grips well and complements the quality of your bottle.
  • Comes with DayCap cap and removeable filter cartridge.

    *Includes Giardia, Cryptosporidium, E. coli, Salmonella and Cholera.

2.6 oz
0.07 kg
2.8 in
7.1 cm
3.9 in
9.9 cm
4.2 in
10.6 cm
Hollow Fiber
1 liters per min
1000 liters
Made in U.S.A. of U.S. and Imported Materials
With which bottles is my DayCap compatible?
The DayCap is compatible with the following wide-mouth water bottles: Nalgene® Wide Mouth, Hydro Flask® Wide Mouth, Yeti® Yonder™, CamelBak® Wide Mouth.
How often should I clean my DayCap?
That often depends on the clarity/quality of water being filtered. However proactive cleaning will keep your filter flowing faster for longer. Use your best judgement but consider quickly shaking it clean each time you fill your bottle with dirty water.
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.
Will the DayCap filter remove unpleasant tastes?
No. Hollow fiber filter media does not remove tastes from water.
How do I disinfect my DayCap filter?
To disinfect your DayCap Filter and water bottle, make a bleach solution in the bottle by combining 3mL (or approx. 1/4 tsp) of bleach with 1L of clean/clear water. Then perform a shake-to-clean procedure (see instructions). Then, allow the bottle to sit on its side for 30 minutes, then roll the bottle to the opposite side and allow the bottle to sit for another 30 minutes.
Is the DayCap in-bottle filter dishwasher safe?
The cap component of the DayCap is dishwasher safe. The filter component IS NOT dishwasher safe. A dishwasher cycle will permanently damage filter cartridge and make it unsafe to use.
Is it okay to filter tea-colored water?

Tea-colored water typically has a high concentration of decaying vegetation adjacent to, or in, a water source, resulting in a variety of organic acids. These acids, and the accompanying water conditions, are very hard on ALL types of water filters. Get your water elsewhere if you can.

However, if no alternatives exist, we recommend backflushing/cleaning your filter more frequently, even after each use. This will help minimize the clogging of the filter.

Are there any issues with using the DayCap in-bottle filter in freezing conditions?

A DayCap that has been recently used to filter water will have wet hollow fibers, which can freeze and break the fibers. Broken fibers no longer filter water. It is important to prevent hollow fiber filters from freezing.

If you are expecting freezing or near-freezing temperatures, we recommend carrying or stowing the filter cartridge near your body (e.g., in a chest pocket) and bringing the filter into your sleeping bag overnight. (Place it in a plastic bag to prevent it from leaking).

If you think your filter may have been damaged by freezing, perform a filter integrity check before the next use to determine if it is still safely filtering water (see instructions for your filter product). Consider carrying a replacement filter as a backup in case of a failed integrity test.

What if my DayCap takes a hard drop?
Hollow fibers can break due to impact. Once broken, they will no longer safely filter water. Often your DayCap Filter will be protected from impact by being inside your bottle, but in the event of it directly hitting the ground, perform an integrity check before the next use to determine if it is still safely filtering water (see instructions for your filter product). Consider carrying a replacement filter as a backup in case of a failed integrity test.
Can I get a replacement filter for my DayCap?
Replacement filter cartridges can be purchased here.

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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