Osprey HydraJet 12

We have been taking the Osprey HydraJet 12 (also called the Jet 12) out for hikes and bike rides for the past several weeks. It’s the perfect size for young kids’ daytime adventures.

The HydraJet 12 is extremely well constructed. There has been great attention to details in this redesign of the previous model Jet. The pack has been streamlined and is geared towards active kids wanting a lightweight close-fitting pack.

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Tech Specs

  • Volume: 12 Liters
  • Weight: 0.84 lbs
  • Dimensions: 14.57″H x 9.84″W x 8.27″D
  • Hydration Compatible: Yes, 1.5L reservoir included
  • External Pockets: 3 outer mesh stretch pockets, 1 top zippered pocket
  • Material: 400D recycled nylon packcloth
  • Ages: 4-12

Key Features

  • Dual stretch mesh side and front pockets
  • Small external zippered pocket
  • Lower web-loop daisy chain attachment points
  • External reservoir sleeve with included 1.5L Hydraulics reservoir
  • Wide-mouth bucket-style main compartment opening
  • AirscapeTM Backpanel: Open mesh over bump EVA foam ensures ventilation and comfort
  • Smooth edgeless harness, fleece-lined with no edge seam for a comfortable fit and feel
  • Adjustable sternum strap with rescue whistle

The fleece-lined straps are a really nice touch. Because the straps fit a bit closer to the neck than some of our other packs, this helps keep the wearer comfortable while keeping the pack more secure on the body.

The included reservoir is easy to fill and well-constructed. It’s easy for kids to slip in and out of the external compartment, and the kids enjoy securing it into place with the clip. The bite valve was easy for even my 2-year-old to figure out how to use.

Best Uses for the HydraJet 12 day pack

Day Hiking

A 12-liter pack is a slightly larger daypack than my 6-year-old son and 4-year-old daughter carried previously, but they both transitioned to it easily.

The Jet is a great daypack that would fit lots of ages comfortably. Although it’s suggested for ages 5+, my 4.5-year-old daughter wears it comfortably.

The Osprey Jet series is ideal for day hikes where you just need the essentials, but my daughter will carry it when we backpack this summer. She isn’t ready for a larger pack, and is naturally less willing to hike than our 6-year-old.

Carrying this pack with just her snacks and water will make her feel like she’s contributing without weighing her down.

There’s an included key clip inside which I thought was funny (kids don’t have keys right?) until I ended up using it on a few hikes where my son was packing the gear and I was carrying the girls.


The pack fits very close to the body. Even while biking, it stays secure and doesn’t flop around. The previous version of this pack had a hipbelt, and though my son and I both prefer packs with hipbelts for stability and storage, this one feels very secure without one.

We have a small biking hydration pack that can carry their water and one other small item (like binoculars or a snack), but this pack will be great for longer destination rides where they can pack in a few layers or some drawing materials.

Appearance and Functionality

The pack looks really nice, it’s very high quality. The kids have other Osprey gear and they love the logo, so that’s always helpful to get them excited about carrying their packs!

They have fun choosing a fun item to stuff in the back mesh compartment, which is also useful for stashing a hat or other small item that you may be taking on and off often.

The “powermesh” pockets are awesome. You can easily store and retrieve water bottles from the sides. All three pockets are also great for quickly stuffing snack wrappers in without fear that they’ll slip out.

What Does it Hold?

The pack can hold a lot of stuff! Here it’s packed with things my 6 year old typically carries for day hikes. The 1.5L reservoir is filled just up to 1 liter, some snacks, a puffy vest, a journal, some binoculars, wool mittens and rain mittens.

Because of the low weight of the pack, all this stuff weighs in just under 5 pounds, which is a good weight for an average 5+ year old to carry. Kids shouldn’t carry packs heavier than 10-20% of their body weight, so every ounce the pack weighs counts!

The pack filled with the contents pictured above

The Bottom Line

What we Love

The Osprey HydraJet 12 is a fantastic pack; well designed, looks great, the kids like to wear it.

It has nearly all the features I’d look for in a kids’ pack. While the price of $70 may seem high for a kids’ day pack, the included 1.5L reservoir costs $32 if bought separately, and it can be used with the Osprey Jet 18 also (and with many other hydration-compatible packs). The quality of the pack is worth the investment.

What we aren’t so crazy about

While I love this pack and can’t think of many faults, a lightweight rain cover would be nice. But for packs of this type a rain cover probably adds more weight than usefulness for the average user.

My son and I also prefer packs with hip belts, and this doesn’t have one. However, it does fit very snug against the body without one.

The magnet for the hydration hose clicks into place great, but it doesn’t always stay put unless you loop it through the elastic on the strap. However, this has been my experience with all magnet connections for hydration reservoirs. So, while it’s easy to click into place, the magnet still doesn’t help it stay into place without the elastic.

Most importantly, my kids love this pack and ask to wear it a lot.

Where to buy

The HydraJet is a new pack for Osprey this year, and you can buy it direct from Osprey and from other retailers. The fit is adjustable and should fit most kids over 4 years old.

Therefore, trying it on first to ensure proper fit is less critical with this type of pack.

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  • Kristin grew up in Western Massachusetts but moved north to Alaska in 2008 in search of more snow and bigger mountains. She homeschools her three children and tries to spend as much time as possible learning outside. Kristin loves hiking, camping, puddle stomping, laughing, igloo building, reading, science, baking, photography, and watching the sun go down from on top of a mountain; and is passionate about sharing her enthusiasm for the natural world and her knowledge of the gear that can get you out there in every kind of weather. She works part-time from home as an Environmental Scientist and technical editor.

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