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No, you might not be able to travel through time using this pack, but there's a good chance it's a gift from the future. The Sierra Designs Flex Capacitor Backpack can expand and compress throughout your trip as your needs change, and it does so with lightweight stability. A unique gusset system on the back lets you enlarge the bag to 60 liters at the start of your trip, then tighten it down to 40 liters as your food reserves dwindle and you've moved layers from bag to body.
Whether your trip last two days or seven, you'll be glad for all the places to stash your stuff, thanks to seven different pockets as well as loops on the back for your ice axe. If you're trekking through uneven terrain or might encounter snow, the compression straps can help keep the necessary tools attached, waiting and ready for deployment. A zippered stash on the top of the bag is a perfect hiding place for the vitals you'll need throughout the day, and there's even a spot for your reservoir should you get thirsty.
- Versatile pack for short and not so short adventures into the wild
- Can expand in capacity as you pack and unpack throughout the trip
- Durable ripstop construction fends of sharp rocks and branches
- Y-Flex internal suspension provides torsional load bearing support
- Raised lumbar and scapula pads provide comfort and air flow
- Compression straps can secure snow shovels and trekking poles
- Mesh pocket on shoulder strap for easily accessible water bottle
- Item #SDS009G
What do you think about this product?
March 12, 2019
Very happy with my Flex Capacitor
I purchased my Sierra Designs Flex Capacitor backpack from Backcountry prior to embarking on a 6 day hike of the famous 'Overland Track' in Tasmania, Australia. I was very happy at the performance of the backpack. It stabilised the load very well with the compression straps, and was comfortable and firm to wear. At the end of each day, my back was not sore. It was easy to access with the zip. I liked being able to compress it in further as I ate my way through my food over the hike. I highly recommend this backpack. I love that it works well for weekender getaway hikes as well as multi-day hikes. In fact this backpack will virtually every trip, due to its capacity to expand from 40L - 60L. It's also very light for the load capacity it will handle. No regrets. Recommended.
May 21, 2018
Hip Belt Sizing Help
February 1, 2018
Does It All
I love that this pack can do pretty much anything. I mainly do quick weekend trips but wanted to have a pack that can do the occasional longer backpacking trip. This is such a simple pack that it has even worked well for travel.
November 10, 2017
Super Innovative Pack!
The innovation in this pack is truly incredible. I love that it can expand between 40L-60L, which makes it super versatile. No need to have a weekend pack and a separate pack for weekend+ adventures. The Flex Capacitor can meet the demands of both without really adding weight. Nice work Sierra Designs!
November 1, 2017
Admiring the view!
October 31, 2017
How to fit the Flex Capacitor
October 31, 2017
Flex Capacitor review w/ Andrew Skurka
Check out this great video with Andrew Skurka discussing the thoughts and details behind the Flex Capacitor 40/60 pack.
December 31, 2017
What are the hip belt sizes for each pack?
November 19, 2017
What size waist belt do these packs ship with? I know there are four different sizes. Thanks in advance!