Travel better with the Gregory Inertia 20 3D-Hydro Daypack.

Are you searching for your next favorite travel bag? The Gregory Inertia 20 3D-Hydro Daypack is equipped for everything you need on the go. Designed for grab and go type adventures, it’s just what you need for hikes, city exploration, camping, and a whole lot of other adventures. We appreciate that it’s not only low-profile but durable. You won’t have to worry about this product holding up when you go to hit the trail.

Wondering what to pack can be tricky. Make sure to bring the essentials by season. For the fall and spring, it’s always smart to have a raincoat and a light pair of gloves on hand. Come summer, you can swap those items out for a swimming towel and suit. Here’s the best part. You can leave your bulky water bottle behind. The Gregory Inertia 20 3D-Hydro Daypack comes equipped with a reservoir for convenient hydration on the go.

Gregory Inertia 20 3D-Hydro Daypack Features and Benefits

Okay, let’s dive right in. The Gregory Inertia 20 3D-Hydro Daypack has some pretty awesome features and benefits. In this pack, you will get not only a hydration sleeve but also great storage space for a 20 L bag, ventilation, padding and support, and more.

Hydration Sleeve and 3L 3D Hydro Reservoir

Gregory Inertia 20 3D-Hydro Daypack - Hydro Reservoir

Credit: Amazon

This is one of our favorite features about the Inertia 20 3D-Hydro Daypack from Gregory Packs. It’s just so convenient. Leave your water bottle behind and fill up with the convenient built-in reservoir from Gregory. Three liters is a good amount of water storage. If you are only going on a day’s hike, that should be plenty. However, if you know you will be drinking a lot more, you can supplement the reservoir with an additional bottle of water. And if you’re looking to cut the bulk of extra carrying altogether, bring a filtration straw. 

Ventilated Backpanel

Gregory Inertia 20 3D-Hydro Daypack - Ventilated Backpanel

Credit: Amazon

Nothing is quite as great as having a ventilated back panel in the heat of summer. We’re sure you’ve experienced back sweat when traveling before. Your pack is weighing heavy, you have been carrying it for a long time, and there is still quite a ways to walk before you get to your hostel. That creates a sticky situation. Instead of bearing the heat and discomfort, invest in a pack that supports your needs. With the Gregory Inertia 20 3D-Hydro Daypack, you will stay cool and dry on the trail or wherever you go.


Here is yet another important feature of the Gregory Inertia 20 3D-Hydro Daypack. Travelers often overlook padding when choosing their backpack. But good padding makes a world of difference. After all, you don’t want an aching back and straps that dig into your shoulders. These problems are more common than you would think. The padded, adjustable hip belt and shoulder harness transfer the weight of the pack off of your back and shoulders and down to your hips. Not only is this more comfortable but it also spares you from unnecessary back pain. It is the healthier way to wear a pack.

Exterior Storage

Looking for some easy access storage? The front and side stretch mesh pockets are great places to store items you need in a quick second. Hand wipes, a travel umbrella, and granola bars are a few examples of items you may want to stash here. It’s also a handy place to keep an extra water bottle (if you really need it) as well as an extra layer (think a thin raincoat or windbreaker).

What Travelers Are Saying About the Gregory Inertia 20 3D-Hydro Daypack 

We’ve been through our fair share of packs. And believe us when we say you won’t find another one quite like the Gregory Inertia 20 3D-Hydro Daypack. Travelers love it too, swearing it’s by far the lightest pack they own.

Travelers love the Gregory Inertia 20 3D-Hydro Daypack too. Even when the backpack is fully loaded, you won’t feel tired and weighed down after walking with it on. The hip belt makes it very comfortable to wear and the hip pockets are in a good location for easy access to items you may need.

In addition to the durable quality, the interior is so spacious. With interior dimensions of 20 liters, you will have plenty of room for the gear you need to bring. If you are considering investing in a high-quality backpack for the great outdoors, this is it. It’s not only highly adjustable but it also offers customization for nearly any physique. Gregory Inertia 20 3D-Hydro Daypack offers plenty of informative videos to walk you through the features and adjustments so you will get the right fit.

Do you ever find yourself constantly readjusting the weight of your pack to make sure shoulders and hips to stay comfortable? You won’t have to do that here. The hip belt and internal frame shift the weight of the backpack off of your back and shoulders to your hips on its own. Another great thing about this pack vs. a duffel bag style is that with frameless packs, you don't need to use any padding between your pack and back. This offers you a lot more options for sleep pads and sleep systems. It’s also nice knowing that you won’t be sweating through the material of my pack because it doesn't ride directly against my back.

The ventilation of the mesh helps your back breathe better. You can easily fit all your gear, food, and water for the day in it. Anything over a hike’s worth would require a resupply. For weekend backpackers, day hikers and car campers we could see where this pack could be sufficient. However, if you aren't a minimalist this pack isn't going to be big enough to get you through a day. We encourage people to consider buying a smaller pack challenge yourself to limit what you can fit in this pack.

Really experience nature, leave all the technology and comforts behind. Before you pack it, ask yourself am I really going to use this? Trust us. Overall,  travelers are happy with their purchases and consider this investment to be money well spent.

Alternative Daypacks That May Work Better for You

Osprey Escapist 32 Daypack

Osprey Escapist 32 Daypack

Do you find yourself needing a bit more room? Perhaps you are going on a longer, more strenuous hike and need to bring more food and gear? If so, you should consider this larger one from Osprey. With 32L, you will get much more storage room. But don’t worry. That doesn’t mean you need to be weighed down. Anchored by a bio-stretch harness and hip belt, this low-profile pack is made to keep you balanced with a heavy load – even when descending the roughest terrain.  Thanks to the airscape mesh back panel, you’ll stay cool and dry even when you’re grinding up a mountain pass.

Let’s take a look at how to pack and access your items. The main compartment has a convenient zippered front panel, so you can see all of your gear at once. In addition, a zippered divider at the base of the pack provides optimal storage. There are plenty of external storage options. Three handy stretch mesh pockets offer ample room for snacks and your electronics. The hip belt also offers twin zippered pockets. You’ll never run out of storage room with this bag. That’s not all. A zippered external front pocket is designed especially to keep valuables secure. You don’t have to worry about scuffing up that favorite pair of sunglasses anymore.

This brand offers several Escapist models in varying sizes. However, we’re convinced 32 liters of storage is the way to go. It’s large enough for you to easily fit your sleeping bag, a bivy sack, a spare set of clothes, reusable water bottles, a large hydration bladder, energy bars, accessories, and electronics in it. And there’s still ample space leftover.

Size matters for daypack storage. But it’s not everything. A good pack should help you carry your essentials but you also need to know what qualities you’re looking for. I’m happy to say that the Osprey Escapist 32 Daypack fares well in my book. There’s a nice mid-sized compartment with multiple pockets for tools, bike pumps, and everything in between.

Tech Specs:

  • Durable nylon material
  • 32L of storage space
  • Plenty of external storage compartments
  • Airscape back panel
  • Sleeping bag compartment
  • Lidlock helmet attachment
  • Blinker light attachment
  • Scratch-free pocket
  • Zippered harness pocket

Enjoy Smooth Travels with the Gregory Inertia 20 3D-Hydro Daypack

The next time you pack up for the backcountry or city life explorations, do it right. The Gregory Inertia 20 3D-Hydro Daypack is just the versatile, durable pick you need. Made to withstand the ups and downs of travel, it offers the perfect amount of packing space and a lightweight body so you won't feel weighed down while you're on the go. The suspension system and smart features like padded back and shoulder pads help to distribute weight well and spare your back and shoulders. This is one of our favorite styles for daypacks.

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