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Traveling or trekking? The men's Gregory Inertia 18 H2O hydration pack transitions from trail to transit with zippered pockets and a reservoir compartment that converts to a small laptop sleeve.
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Imported.
View all Gregory DaypacksBest Use | Hiking |
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Frame Type | Frameless |
Gear Capacity (L) | 18 liters |
Gear Capacity (cu. in.) | 1,098 cubic inches |
Reservoir Compatible | Yes |
Reservoir Included | Yes |
Bottle(s) Included | None |
Liquid Capacity (L) | 2 liters |
Liquid Capacity (fl. oz.) | 64 fluid ounces |
Weight | 1 lb. 3.5 oz. |
Fits Torso Length (in.) | 16-21 inches |
Fits Waist/Hips | 28-48 inches |
Material(s) | Nylon |
Pack Access | Panel |
Number of Exterior Pockets | 3 + main compartment |
Hipbelt | Yes |
Bite Valve Shut-off Switch | Yes |
Raincover Included | No |
Dimensions | 19 x 10 x 8 inches |
Gender | Men's |
Sustainability | Contains recycled materials |
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30 miles down with this thing on my back. I was in and out of Yellowstone and the Tetons this last week and did put over 30 trail miles on this bag. I am very impressed with how it performed. It was lightweight, comfortable and super easy to use. The hydration pack was perfect and very intuitive to use while filling up or on the trail - the magnet attachment to the chest strap is just a gem. I also love how the chest strap has a magnetized closure which makes it easy to use, again, and quite secure. The main pocket was the perfect size for me, I was able to fit a rain jacket, lightweight fleece, snacks, bug repellent, sun protection, snacks and a few other goodies with room to spare. It helped me to feel prepared for whatever might come my way, and when the rain came I was prepared! The pockets are easy to open and the small ones can store all my little goodies, which I love. The shoulder straps were supportive and very lightweight which helped it to be comfortable to wear for hours on end, I never really wanted to take it off! This comes with a thin waist strap that I don’t feel like was super helpful on this size of bag, buckling it in definitely helped put some of the little bit of weight I was carrying on my hips but I didn’t think it was very necessary. If the straps were thicker or more substantial, I might like them better. But I do like that they are removable. Maybe that could be combined? This was the perfect size for my needs and doing several daily hikes. It is good to just grab and take with you on any adventure you’re eyeing. Thanks Gregory for such a well made bag!
I like the fact that this pack has three outer mesh pockets, one 3L water reservoir compartment including hose routing straps, and a comfy breathable meshed back support plus shoulder straps. I WOULD LOVE this pack if it had one additional inner pocket for keeping valuable electronics and wallet away from easy reach and thieves. I WOULD ALSO LOVE this pack if it had a single-handed, quick-pull draw cord with a weather flap seal in order to access the MAIN COMPARTMENT without the use of a cumbersome zipper, which slows me down when in outdoor conditions. Other than that, this pack is beautifully made.
I love this pack for day trips, both hiking and snowshoe. The bladder is easy to access, fill, and secure. The main compartment has sufficient space for a first aid kit, food, wind/water proof shell with room to spare. I only wish that it had a better means to secure snow shoes for hikes where they are not initially needed.
At first glance I thought this hydration pack would be an improvement on the one I’ve been using the past couple years. The backpack itself is roomy and well designed. I stuffed a 7.5-inch yoga mat into it (it sticks out the top, of course, but that gives you a sense of the storage room). There’s an additional small zippered pouch at the top, and a mesh pocket on the left side that can hold t-shirt or a small towel, and a zippered pocket on the right side that fits a large phone and keys. Excellent zipper pulls. Durable setup all around. But this is a hydration pack, so I’ll focus on that aspect. Great design on the reservoir (bladder) itself. It is really easy to remove, fill and replace (which is not true of some competing models). The hose can be easily disconnected from the reservoir, which is handy. There’s a nifty interior hanger in the backpack, so the reservoir does not just slumped at the bottom. When empty and open, the reservoir doesn’t flatten out, so that the inside can dry. The reservoir holds 2 liters — adequate for relatively shorter workouts and/or cooler days. My other water pack holds 3 liters, and while I don’t always fill it, there have been times when I need 3. The backpack is plenty big enough to hold a 3-liter reservoir, so I wonder why they chose to limit it to 2 liters. There are three design flaws with the water-delivery system. 1. The mouthpiece has a magnet that’s supposed to stick to a corresponding small one on the chest-strap buckle. When the hose emerges from the right side, the angle does not allow the magnet to stick. I tried many times and the force of the curved hose pulls it off immediately, every time. If the hose is switched to emerge from the left side, the magnet sticks, but the connection is weak and it dislodges easily. 2. The hose is too short to use from the right side. Given that the magnet does not work, you can instead clip the hose into a front clip (which exists on the right side only), but in that configuration, I had to crane my neck forward and to the side to get a drink from the remaining short bit of hose. If you don’t use the front clip, the hose is long enough, but now it hangs free unless, as a workaround, you stuff it up under the chest strap. However, in this configuration, given the angle that the hose exits the backpack behind your neck, the hose wraps around the outside of the shoulder, at the top of the bicep. It’s functional, but annoying. All this is avoided if you bring the hose out from the left side, so consider this a preference. 3. The mouthpiece has a 90-degree bend, so it must be turned the right way to get it in your mouth. This isn’t hard, and no big deal when hiking. But when biking, it can require a little blind fumbling, an extra frustration compared to one that goes straight in. I tried twisting the hose every which way upon attaching it to the reservoir, to change the default angle, and still had to muss with it each time I wanted a drink. Bottom line: This is a well-built backpack with some clever design elements, but it has serious flaws with its primary function, at least for bikers — fix those, and this would be a 5-star product worth the price. As is, I definitely would not recommend it for biking. Hikers might find the flaws less annoying and appreciate the roomy main compartment and handy pockets.
[This review was collected as part of a promotion.] I did receive this pack as a #giftedproduct, but that in no way influences my review or remarks. I have been a huge fan of Gregory for years. I use their bags for backpacking, day hikes, and commuting. Their bags are top-notch quality, feature-rich and comfortable. The Inertia 18 is no exception. Why do I love it? The small footprint gives way to a massive amount of capacity without feeling too bulgy. The bag itself has a shape that it doesn't lose when empty - making it easy to pack up, sort through, and clean up. It's got all the bells and whistles that can be jammed into a small package: Amply sized main storage compartment, a separate hydration pocket, a front knickknack pocket at the top, a mesh water bottle side pocket, and a bonus zip pocket on the other side. The back panel mesh on the back allows pretty good airflow, and the straps are nice and lightweight so they don't feel too bulky or heavy - even when the sweat hits. But the gem: The hydration system. Gregory absolutely killed the game with their hydration systems - hands-down best on the market. This bag comes with a 2L bladder which is the perfect size for most hikes that I do. On hot days, I will throw an iced-down water bottle in the side pocket. (I Live in AZ). The bladder has a quick release system meaning you can completely pull it out to fill it up. So easy and clean. It has a wide mouth to make filling simple. There is a handle to help carry the bladder outside of the bag. The lid twists on and off with ease and is very secure - which is where many other brands go amiss. The INertia's hydration compartment has a built-in hook to hang the bag from so it doesn't slump around, and because of the hardened back panel of the bladder, it stays in place - and keeps that water upright and ready to flow. It's also the simplest water hydration system to clean. Gregory integrated a hook for you to be able to hang the bladder upside down. I usually throw a paper towel or small towel in the bottom to soak up any water, making sure to keep the mouth open for airflow while the bladder dries itself out.
I purchased this daypack for 7 days of hiking in Yosemite. Inside the pack, I carried a full water bladder, 1 fleece hoody, 1 rain jacket, 1 wind shirt, 1st aid kit, snacks and a small pair of binoculars. On the outside, I attached my hiking poles and a full 1 L Nalgene bottle. I am 5'11 and weigh 180 lbs. The pack fit me really well once I dialed it into how I like to wear a daypack. I removed the hip belt because it wasn't a feature that I wanted to use. The pack carried my loadout of 15 lbs nicely. The shoulder straps are minimalist-style but are still comfortable. I only experienced shoulder fatigue after 8 or 9 hours of use on my longer days on trail. Overall, I am really pleased with this pack. I tried on several daypacks before I made the purchase and I feel like I got exactly what I was looking for.
This is a fantastic and comfortable day pack. I have used it on a few hikes and it has been awesome. The mesh panel helps with breathability, but if you run hot you’ll still sweat with this pack. I love the separate hydration sleeve and the clip that keeps the hydration pack steady. The hydration pack it comes with is amazing and easy to clean. The only think that could make it better would be a rain cover to go with the pack.
Great pack, initially felt stiff, now that it's broken in and been roughed around the city and the back of the truck for a few weekends, fits much better. I use this for a bike commute to work, enough room to put a change of clothes in, water bottle and a little bit of food for the day, the added bonus of hydration bladder is great for the commute to and from and not have to worry with a water bottle.
This H2O backpack is awesome in every aspect. Quality materials, great fit and many options.