HydraPak Stow Collapsible Water Bottle, 1 L, Glacier Blue (GS351GB)

Overview: who it's for

The HydraPak Stow 1 L is a soft, collapsible water bottle. Full, it holds a litre (32 fl oz) and stands roughly like a flask, helped by an internal baffle that keeps it slim. Empty, it flattens and rolls up around its own handle into something the size of a folded sock. HydraPak lists it at 1.8 oz.

That's a different job from every other bottle in our drinkware category. The insulated steel bottles keep water cold. The Stow keeps water capacity available without taking up space. In a van that means a spare litre for a hike, an extra bottle for a guest, a backup if a jug cracks, or a bottle that threads onto a squeeze filter.

What the Amazon link sells: the HydraPak Stow Collapsible Water Bottle, 1 L, in Glacier Blue, part number GS351GB. That part number matches the current Stow 1 L on HydraPak's own site. An older Stow 1 L with a different part number (GS330 series) is still listed on Amazon. This review covers the GS351 version we link to.

This review is research-based. VanLifeKitchens doesn't test products hands-on. Specs come from HydraPak's Stow 1 L product page and from the Amazon listing we link to.

Choose this if:

• You want a spare litre of water capacity that takes almost no room when empty.
• You hike from the van and want a light bottle that fits a pocket.
• You use a 28 mm threaded squeeze filter and want a bottle to fill and squeeze through it.

Skip this if:

• You want cold water to stay cold. The Stow isn't insulated.
• You want a bottle for hot drinks. It's a soft TPU bottle, not a flask.
• You want one everyday bottle that takes knocks on a dashboard. A rigid steel bottle is tougher.

What it is

The Stow is made of TPU (thermoplastic polyurethane), with a polypropylene (PP) cap and a silicone nozzle, according to HydraPak. TPU is the flexible, rubbery plastic used in many soft flasks and hydration bladders.

The cap and nozzle. On top is a self-sealing silicone nozzle. You squeeze or suck to drink, and the slit closes again when you stop, so it doesn't drip if it tips over. A flip-top cover protects the nozzle from dirt. HydraPak calls it a "high-flow self-sealing silicone nozzle," designed for "splash-free drinking on the move."

The baffle. Inside the 1 L size, HydraPak adds an internal baffle that "adds structure, makes it easier to hold, and provides a slim profile when full." HydraPak notes that the baffle is on the 1 L Stow only, not the smaller sizes.

The bail handle. A flexible loop near the cap is for carrying, clipping to a pack, and holding the bottle while you fill it in a stream. When the bottle is empty and rolled up, it stows into the handle.

Specifications and sources

HydraPak's page also lists dimensions of 190 x 150 mm. That figure appears in the same spec block across the Stow range, so we can't confirm it's the 1 L's size. The Amazon listing's dimension fields look like packaging data. Plan on a bottle roughly the length of a standard 1 L bottle when full and much smaller rolled.

What HydraPak's page doesn't say. It doesn't publish a maximum water temperature for the Stow on the page we checked. Retailers often quote a limit for HydraPak soft bottles, but we haven't seen it from HydraPak for this model, so we won't repeat it. Treat the Stow as a bottle for cold or room-temperature water and don't fill it from a kettle.

How it fits van life

Space. This is the reason to buy one. A rigid 32 oz insulated bottle such as the Hydro Flask Wide Mouth takes the same cabinet space whether it's full or empty. The Stow rolls up. Two or three of them fit in a drawer corner and give you two or three extra litres when you need them: for a day hike, for guests, or for carrying water from a campground tap to the van.

Water treatment. HydraPak says the Stow "attaches to most 28MM threaded water filters." Our Sawyer Squeeze review notes that Sawyer says its threads fit standard 28 mm bottles. Screw a 28 mm filter onto a full Stow and you can squeeze water through it into a cup or a clean bottle. HydraPak and Sawyer don't publish a compatibility list for this exact pairing, so check the fit when it arrives. The Katadyn BeFree comes on its own wide-mouth soft flask and isn't a 28 mm thread.

A filter is not a purifier. Most squeeze filters are rated for bacteria and protozoa, not viruses, chemicals or salt. Our water filtration guide explains the difference and what each type does not remove.

Clean and dirty bottles. If you use the Stow as the "dirty" bottle you fill from a stream, don't then drink straight from it without a filter. Some people keep two Stows in different colours, one for untreated water and one for treated water. That's a simple habit that avoids mixing them up.

Heat. Without insulation, water in a soft bottle warms to the temperature of wherever you leave it. A bottle on the dashboard in summer gets hot. Keep it in the shade, in a cooler, or in the van's coolest cabinet. If you want cold water all day, carry an insulated bottle or the YETI Rambler Half Gallon Jug and use the Stow for spare capacity.

Freezing. The listing says the Stow is freezable. A partly filled, frozen Stow doubles as an ice pack in a cooler and becomes drinking water as it melts. Leave room for expansion: water expands as it freezes.

Taste, cleaning and care

Some owners report a plastic taste or smell from the bottle, a common complaint about soft TPU bottles when they're new. Rinsing and filling with water a few times before the first trip is the usual approach. If taste matters to you more than packability, a stainless bottle avoids it entirely.

The listing says the bottle is dishwasher safe. With limited water in a van, these habits help:

• Only put water in it. Sports drinks and juices leave sugar that's hard to clean out of a soft bottle with a narrow neck.
• Dry it open. Leave the cap off and let the bottle air out before rolling it up. Rolling a damp bottle is the quickest way to get a musty smell.
• Clean the nozzle. The silicone nozzle has a slit that can collect residue. Rinse it with the cap off.

Punctures. A soft bottle can be holed by a sharp edge, a fishhook or a knife in the same drawer. TPU is tougher than it looks, but store it away from sharp tools. HydraPak's Beyond Lifetime Guarantee covers manufacturing and material failures, and HydraPak says it will repair or replace the item for free in that case. Punctures from accidents aren't a manufacturing defect, so check the terms.

Limitations

• Not insulated. Water warms in a hot van.
• Not for hot water. HydraPak doesn't publish a temperature limit on the product page we checked, so keep it to cold or room-temperature water.
• Can be punctured. Store it away from sharp edges.
• Possible plastic taste at first, which some owners report.
• Squeeze drinking. Some people prefer the flow of a wide-mouth bottle.

Alternatives on this site

• Hydro Flask 32 oz Wide Mouth (review): insulated stainless with the same capacity, but rigid and much heavier.
• Owala FreeSip 24 oz (review): insulated with a straw lid. Better for daily drinking while driving.
• Katadyn BeFree 1 L (review): a soft flask with a filter built into the cap. Choose it if you want filtering and drinking in one.
• Scepter 5-gallon container (review): bulk water storage for the van itself.

Verdict

The HydraPak Stow 1 L is a simple, very light way to add a litre of water capacity that disappears when you don't need it. HydraPak lists it at 1.8 oz, says it fits most 28 mm threaded filters, and backs it with its Beyond Lifetime Guarantee for manufacturing defects. It isn't insulated, isn't for hot water, and needs to be kept away from sharp edges. Use it as a spare bottle, a hiking bottle or the bag you squeeze through a filter. Keep an insulated bottle for cold drinking water.

FAQ

Is the HydraPak Stow insulated? No. It's a single-layer soft TPU bottle. Water inside will warm or cool to the temperature around it.

Can I put hot water in the HydraPak Stow? HydraPak's Stow 1 L product page doesn't publish a maximum temperature. Treat it as a bottle for cold or room-temperature water and don't fill it from a kettle.

Does the HydraPak Stow fit a Sawyer Squeeze? HydraPak says the Stow attaches to most 28 mm threaded filters, and Sawyer says its Squeeze threads fit standard 28 mm bottles. Neither publishes this exact pairing, so check the fit.

How much does the HydraPak Stow 1 L weigh? HydraPak lists it at 51 g (1.8 oz). The listing says under 2 oz.

Is the HydraPak Stow dishwasher safe? The Amazon listing says it is dishwasher safe and freezable.

Does the HydraPak Stow taste like plastic? Some owners report a plastic taste or smell, especially when the bottle is new. Rinsing and filling it with water a few times before use is the usual approach. A stainless bottle avoids the issue.

What warranty does HydraPak offer? HydraPak's Beyond Lifetime Guarantee covers failures due to manufacturing or materials, which HydraPak says it will repair or replace for free.

Sources and verification

• HydraPak, Stow 1 L product page and variant data: 1 L / 32 fl oz, part numbers GS351 (including GS351GB), 51 g / 1.8 oz, TPU, PP and silicone, self-sealing nozzle with flip cap, internal baffle on the 1 L only, most 28 mm threaded filters, bail handle, Beyond Lifetime Guarantee. https://www.hydrapak.com/products/stow™-1l (checked 2026-10-11)
• Amazon listing for ASIN B0G6NHPQFH, the listing this review links to: title, part number GS351GB, 1 L, under 2 oz, dishwasher safe and freezable, 28 mm filter kit compatibility, availability (checked 2026-10-11)