In news coverage this week from the Outdoor Retailer tradeshow, you may hear about two Sierra Designs products with which I’ve been deeply involved: the High Route Tent 1FL and the Flex Capacitor 40-60 Pack.

The High Route Tent 1FL (HR1) was my brainchild and is nearly old news if you regularly read this website. A 110-unit early production run is available now for pre-order directly from Sierra Designs, and will ship early this month. Next spring you’ll see wider retail distribution.

The Flex Capacitor 40-60 Pack was already in the works when I joined SD nearly two years ago. The original design by Casey, Chase, and former SD brand manager Michael Glavin had three things going for it:

Easily accessible interior using a zippered top lid;

Simple, lightweight, and stiff Y-shaped suspension made of tubular aluminum; and,

Adjustable volume using a unique front-side gusset.

My involvement was in perfecting these features (e.g. What zipper should be used on the top lid?) and in designing and making decisions about pockets, fabrics, padding, compression, fit and other details. I also extensively field-tested the prototypes, mostly in Colorado and Utah. Most notably, I used it to pack out an elk last October, making two trips with 69 and 60 pounds; my partner carried the rest.

Availability

A small production run (195 units, I’m told) will be available in early-October, directly from Sierra Designs. Bulk production will arrive in Spring 2017, and hopefully a retailer near you will carry it.

Product specs

$200 MSRP

2 lbs 8 oz (size S/M)

Volume: 40 to 60 liters, using the adjustable gusset

Y-staked tubular aluminum suspension, anchored directly into the hipbelt

Generously sized pockets: Two side pockets Two hipbelt pockets One shoulder strap pocket One top lid pocket

Durable fabrics throughout: Body fabric: 100d ripstop nylon with UHMW reinforcement, aka Dyneema Bottom fabric: 420d nylon oxford Side pockets: partial use of heavy-duty stretch mesh

EVA foam lumbar and scapula pods

Two removable compression straps

Removable hydration sleeve

Two ice axe loops

Sizing

The small production run available in October 2017 will come in three sizes: S, M, and L.

Sizing for Spring 2017 bulk production will be consolidated: small/medium (17”-19”) and medium/large (19”-21”). I recognize that this is a limited size assortment, but I believe that SD wanted to validate the pack first before expanding the SKU count into lower volume sizes.

The hipbelt is interchangeable and, again, there are two sizes: 30″-44″ and 32″-46″.

Optimal uses

For most backpackers, the Flex Capacitor will be a one-pack quiver. Its load-carrying capacity and 60L maximum volume make it suitable for week-long 3-season trips with a bear canister, like a section-hike of the JMT or Kings Canyon High Basin Route.

But at just 2.5 pounds and with a minimum volume of 40L, it is entirely appropriate for a long weekend as well, like the 28-mile Aspen Four Pass Loop.

Regardless of trip length and base weight, I think all users will appreciate its feature set, durable construction, and $200 price.

Naturally, the FC has limitations. For overnights and gram weenies, it’s overkill. And for multi-week expeditions and dedicated meat-hauling, it’s small and skimpy.

The Flex Capacitor should perform well in hot and humid environments. Airflow through the back panel is on par with the “trampoline” packs that normally weigh 5+ pounds. But pick your tradeoffs: because it sits off the back some, it does not “hug” the user like, say, a well designed frameless pack.

Volume adjustment

A unique and beneficial feature of the FC is its adjustable front-side gusset that allows the pack volume to be expanded or collapsed, between 40 and 60 liters. This greatly increases the pack’s versatility, almost a two-packs-in-one proposition. Some photos:

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