The Granite Gear Perimeter 50 is a lightweight backpack that weighs slightly more than 3 lbs and has an adjustable torso length, an adjustable length hip belt, and an internal frame capable of carrying 40-pound loads with ease. It’s set up like most of Granite Gear’s backpacks, with a long front mesh pocket and compression straps on three sides which make it easy to carry awkwardly shaped gear on the outside of the pack. But instead of a top lid or a roll-top like Granite Gear’s other packs, the Perimeter has top and bottom “flaps pockets”, that provide additional storage and attachment points for carrying bulky gear.
Specs at a Glance
- Gender: Available in Men’s and Women’s models
- Type: Internal frame
- Top Closure: Flap pocket
- Adjustable Torso Length: Yes
- Adjustable Hipbelt Length: Yes
- Back Ventilation: No
- Canister compatibility: Internal vertical, On-top under flap
- Weight: 49.6 oz / 1406 g (Actual weighed – 53.1 oz /1505 g)
- Removable top flap pocket (2.1 oz / 59.5 g)
- Pockets: 8 total (4 open, 4 closed) including 2 on the hip belt
- Materials: 100-denier and 210-denier Robic nylon
- Regular Torso: 18″ – 21″ (46 – 53.5 cm)
- Long Torso: 21″-24″ (53.5-61 cm)
- Fit Hips: 26-42 inches
Backpack Storage and Organization
The Perimeter 50 is organized like most Granite Gear Packs with a large main compartment, a long front mesh pocket, and two side water bottle pockets. The main compartment has a hydration sleeve inside and a long extension collar that provides extra capacity beyond the 50 liters specified for the pack. There a few additions to the basic design though: what I’ll call top and bottom flap pockets and a smaller stretch pocket positioned above the front mesh pocket. More about these below.
The main compartment closes with a drawstring and two webbing straps that run from back to front and side to side. Both of these webbing straps are also extremely long so they can run over and compress the top of the pack if you manage to fill the extra capacity of the extension collar. They’re very awkward to manage if you don’t fill the top of the extension collar, however, and flop along the side and back of the pack.
Mesh Side Pockets
The Perimeter’s side pockets are large enough to hold two one-liter bottles and deep enough to hold two Smartwater bottles without having them fall out when you put the pack down. But you can’t reach the side pockets to pull out or replace a bottle when wearing the pack, so you’ll have to put it down or use a hydration system instead.
The side pockets have a compression strap that runs outside them, which makes it difficult to compress the sides of the pack if something like a water bottle is in the pocket. I find this puzzling. Granite Gear was one of the first backpack makers to let you run the compression strap through slits along the sides of the pocket so you could still use it to hold a water bottle and compress the side of the backpack. That feature is missing on the Perimeter 50.
Front Mesh Pockets
The Perimeter has a long front mesh pocket that’s good for storing loose layers and damp items you don’t want inside the pack like a water filter. There’s a second shorter mesh pocket positioned above it that can be used to store smaller items. For instance, it’s perfectly sized to hold a mug-based cooking system, but the pocket is not deep enough to ensure that items don’t pop out and there’s no way to secure the top of the pocket. I use it to stow the extra-long straps used to close the top of the pack, so they don’t flop around.
The Perimeter has two new design elements that I’ll call flap pockets. These are flaps of fabric that fold over the top and bottom of the main compartment and have zippered pockets in them.
The Top Flap
The top flap is a floating flap, a lot like a floating lid, in that it can be raised or lowered to hold bulky objects against the top of the main compartment. It has a zippered pocket that can be used to hold a map, electronics, or other personal items like a top lid, although the pocket is narrow and low volume.
Since the top flap is floating, you can also secure a full-size bear canister to the top of the pack with it and one of the long webbing straps designed to loop over the extension collar from front to back. If your canister is slippery on the outside, like the Garcia shown here, you may want to add some rough patches to it (like sandpaper) so it doesn’t slip out from under the flap or the webbing strap.
In practice, my preference is to remove the top flap pocket and hike without it, because it makes it easier and faster to access the main compartment.
The Bottom Flap Pocket
The bottom flap is like the top flap pocket but it’s not removable. It folds over the bottom of the pack, even though it’s already reinforced with heavier-duty robic nylon. Like the top flap, it also has a zippered slit-like pocket, best suited for carrying a pack cover, which is not included with the pack. If you want you can wedge a foam sleeping pad like a NEMO Switchback between the bottom flap and the backpack. But the straps securing the bottom flap to the pack aren’t long enough to secure larger objects, like some of the two-person tents I tried.
I just don’t understand why all this extra material is needed for this extra flap. Many backpacks come with two webbing straps to secure a pad or tent to the back/bottom of a pack. You can even remove those straps on some packs if they’re not needed. They’re a lot more functional than this extra flap of fabric.
Backpack Frame and Suspension
All of Granite Gear’s backpacks tend to have a different frame system and the new Perimeter 50’s frame is no exception. The frame consists of a spring steel rod that runs a full 360 degrees (hence the name Perimeter) around a rigid PE board covered in fabric. The PE board has webbing loops attached to it corresponding to torso lengths marked in 1″ increments.
Adjustable Torso Length
The Perimeter’s shoulder straps connect to the webbing loops with gated buckles that are opened with a squeeze, making it easy to adjust the pack’s torso length. You can also adjust the width between the shoulder straps, by attaching the buckles to the inner (orange) or outer (red) line of webbing loops on each side of the back panel. The pack’s load lifters are attached to the pack bag at the top of the frame and are effective at pulling the load forward as needed.
S-Shaped Shoulder Straps
The shoulder straps are S-shaped, so they’re well suited for any chest type, including men or women. There’s also a short segment of webbing between the padded portion of the shoulder strap and the torso length adjustment buckle that connects it to the webbing loops, allowing the strap to swivel and accommodate curved chests.
The front of the shoulder pads have daisy chains sewn to them so you can easily attach accessory pockets or bottle holders to the shoulder straps. The pack’s sternum strap is anchored to the daisy chains and can be adjusted for comfort. It’s not the easiest thing to do with the webbing strap connectors used, but you only need to do it once. The sternum strap buckle used on the Perimeter 50 is also much easier to close than the buckle used on other Granite Gear packs in recent years, which is a welcome change.
Adjustable Length Hipbelt
The Granite Gear Re-Fit hipbelt is adjustable for hips ranging from 26″ to 42″ in circumference. This latest version of the hipbelt was modified to fit an even wider range of waist sizes so more customers could use the pack immediately without having to wait for a larger-size replacement, which can be ordered from Granite Gear. It’s secured behind the lumbar area with velcro and takes a little bit of elbow grease and patience to remove and replace.
The inside of the hip belt has printed directions for adjusting the hipbelt length. It’s well-padded on the inside and provides a great fit when it’s been fitted properly. See our article on How Should a Hipbelt Fit? for tips on where the padded sections of a backpack hipbelt should sit on your hips for a proper fit. The hipbelt comes with two large zippered pockets made with solid fabric for better durability. They’re large enough to fit your electronics, snacks, and other smaller items.
The Perimeter hipbelt closes in front with pull-forward straps and a beefy plastic buckle. However, the webbing straps at the end of the hipbelt are extremely long and awkward, to say the least. The problem with these long webbing straps becomes immediately apparent when you whip out your wang-dang-doodle or female urinary director and take a whiz (they get wet.)
While you might be tempted to cut the webbing down, doing so will remove the sewn flap that prevents the strap ends from being pulled through the center buckle. You really want those sewn ends there because it is a real pain in the ass to have to rethread the buckle if the webbing strap pulls out accidentally. The only way to do that after shortening them with a scissor is to sew the flap down again by yourself (or by sticking a safety pin at the end of the strap) so it can’t pull through the center buckle.
External Attachments and Compression
The Perimeter 50, like all of Granite Gear’s multi-day backpacks, makes it easy to attach bulky gear to the outside of the pack using the compression straps on the sides and front of the pack. For example, it’s easy to use the lash a foam pad to the top of the pack (even if you remove the top flap pocket) or lash a pair of snowshoes to the sides or front of the pack in winter. The addition of the top and bottom flap pockets on the Perimeter 50 helps extends those capabilities, but the pack has plenty of attachment points without them as well.
Comparable Adjustable Backpacks
|Men's Model||Weight||Women's Model|
|Osprey Atmos AG 65||4 lbs 9 oz||Osprey Aura AG 65|
|Osprey Exos 58||2 lbs 10 oz||Osprey Eja 58|
|Zpacks Arc Haul Ultra 60||1 lbs 3.6 oz||Unisex-only|
|Gregory Paragon 58||3 lbs 8 oz||Gregory Maven 55|
|REI Trailbreak 60||3 lbs 13 oz||REI Trailbreak 60|
|Six Moon Designs Flight X||2 lbs 4 oz||Unisex-only|
|Granite Gear Blaze 60||3 lbs||Granite Gear Blaze 60|
|Osprey Kestrel 48||3 lbs 9 oz||Osprey Kyte 46|
|Gregory Zulu 65||3 lbs 11 oz||Gregory Jade 63|
|Elemental Horizons Aquilo 75||2 lbs 13 oz||Elemental Horizons Aquilo 75|
The Granite Gear Perimeter 50 is tailor-made for people who have a difficult time finding a well-fitting backpack and is easily adjustable to fit right. It’s really quite extraordinary how easy Granite Gear made it to adjust the pack to fit wide-shouldered people and narrow-shouldered ones, people who have big chests or rounded ones, and tall people and not-so-tall ones. The same is true of the men’s and women’s specific adjustable length hip belt, although Granite Gear has offered that in their other packs for several years.
I’m also impressed by the Perimeter’s frame which can carry a lot of weight quite easily. The pack feels great when carrying a lot of extra water, food, and gear as long as you dial in the fit properly. I think you can carry more than the pack’s max recommended load of 40 lbs if you wanted to.
I’m a little less enamored by the rest of the Perimeter 50 which I find a little busier to use than I prefer. The pack has 25 webbing straps, which have been color-coded so you can differentiate between them. Of these, 4 are way too long, but can’t be trimmed manually without requiring extra sewing to prevent the ends from pulling out of their buckles. There are also 25 plastic buckles and 5 zippers.
If you don’t mind all of this extra complexity and value the adjustability and the Perimeter 50’s load-carrying chops, I think you’ll enjoy using the pack. I’d know I’d be interested in a simplified version of the Perimeter 50 without the added top flap and bottom flap pockets and a roll-top instead of the existing drawstring closure. That’d be a pack I would really enjoy using.
Disclosure: Granite Gear provided the author with a backpack for this review.SectionHiker is reader-supported. We independently research, test, and rate the best products. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.