Jet Grey
Jet Grey

Sierra Designs Flex Capacitor 40-60 Pack

Sierra Designs Flex Capacitor 40-60 Pack is rated 4.9 out of 5 by 8.
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4.8 Star Rating

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"In Stock" means this item is ready to ship. Orders placed before 3pm EST using a ship speed of 1 Day, 2 Days, or 3 Days will ship SAME DAY. Orders using 4-6 Day ship speed will ship within one business day.

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Product Description Item No.   10333406

The Sierra Designs Flex Capacitor 40-60 Pack is an innovative, ultralight backpack designed with a focus on versatility, comfort, and durability. What sets this pack apart is its unique compression system that adjusts the volume of the pack between 40 and 60 Liters. Take it with you for a weekend, a week-long trip, or on a thru-hike for several months. Simply use the compression straps to keep your load stable and close to your back as your packed weight fluctuates. The zippered top lid allows for quick and easy in-and-out of the voluminous main compartment. A removable Y-FLEX aluminum frame, and thick EVA foam padded back panel and hip belt make for an efficient and super comfortable suspension system that will surely help keep a smile on your face over long, long distances.

FEATURES of the Sierra Designs Flex Capacitor 40-60 Pack

  • Expandable 40-60L volume (volume varies between sizes)
  • Ultralight weight design
  • 3 torso sizes (non-adjustable)
  • U-shaped top access zipper
  • Zippered stash pocket on lid
  • Removable reservoir sleeve
  • Shoulder strap water bottle pocket
  • Stretch mesh side water bottle pockets
  • Two hip belt pockets
  • Compression straps
  • Ice axe/trekking pole loop

- + Product Specifications
Best Use: Backpacking
Pack Access: Top
Rated 5 out of 5 by from sturdy bag I used the bag this weekend for the first time. It's very comfortable and well built. I would recommend it. The side pockets are handy and there's a good pouch to put your camelbak.
Date published: 2018-06-25
Rated 5 out of 5 by from Great all around pack I wanted a cross between the ultralight stripped down style of a frameless bag and the Cadillac style bells and whistles of an osprey. This pack fits nicely in the middle. Not as comfortable as the ospreys but carries well and is more versatile. I would prefer it have a “shove it” style pocket on the outside but I have learned to adapt. Great product.
Date published: 2018-01-03
Rated 5 out of 5 by from Awesome Pack! I bought this pack just prior to starting the Wonderland Trail in Rainier and it performed incredibly well! It was easy to adjust, super sturdy, and able to accommodate 10 days worth of food and gear comfortably. I was impressed with how it handled about 40+lbs of weight. The pack is well-constructed and surprisingly light. I backpack for a living and am pretty picky when it comes to gear. This is my new favorite piece of gear :)
Date published: 2017-10-28
Rated 5 out of 5 by from Capacity for flex--awesome! Durable, very comfortable (even with heavy loads), simple, and yet supremely adjustable. Quite light, too. Make sure sure you double check waist measurement and order correct size of hip belt. Very durable and comfortable belt system.
Date published: 2017-10-22
Rated 4 out of 5 by from Great Features Im just giving the pack 4 stars so far as I have not used it on a back packing trip yet. The 4 stars are for the design, weight, and features. I'll update review after a trip or two.
Date published: 2017-09-18
Rated 5 out of 5 by from Awesome pack Purchased this for my upcoming JMT trip. Really enjoy the expanding feature. Took it along for the summit of Mt Baldy this last weekend and it performed awesome. Keeps the weight centered right where you want it.
Date published: 2017-06-01
Rated 5 out of 5 by from Super light and well thought out I have several different backpacks and decided to get the Flex Capacitor as a light weight option for light hiking but I soon realized it can do anything I need it to do and it quickly became my preferred bag. The suspension design is excellent and air flow to your back is the best. You can definitely feel Andrew Skurka's design influence because everything has been very well thought out...Very interested to see what they do in the future to make this pack even better!
Date published: 2017-04-22
Rated 5 out of 5 by from Unbeatable Multi-Purpose Pack I've been waiting for this pack to be released for some time now and have read a lot about it on Andrew Skurka's blog. Although I have not taken it for a trip yet, I CAN speak to the quality of the craftsmanship and materials used along with design principles. I usually backpack with an Osprey Atmos and love that pack, but was looking for something much more simple and a lot lighter. My Osprey is close to 5 lbs where this pack is closer to 2.5 lbs. I'll take that weight savings every day of the week! The water bottle pocket on the right shoulder harness already seems like a no-brainer. Even if all you are doing is using a bladder, you can still use that pocket to store the hose so it's not collecting dust and dirt before it's put in your mouth. I'm also already a fan of the idea that the pack can be tightened up after loading - no one likes shifting weight when walking long distances. I know a lot of packs can crumple or become uncomfortable under heavier loads too. The FC has been tested with loose loads up to 70lbs and still performed comfortably. You can see a video of this on the Sierra Designs website. I find the fit of the pack to be excellent when loaded up. The straps are all simple to adjust and do not require a second person to assist with adjustments which will be super convenient when doing long trails by myself. I'll try to remember to come back and update the review once I've had a chance to take it for a spin. Thanks!
Date published: 2017-04-07
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Do you offer the different hip belt sizes that are usually provided by Sierra Designs?

Asked by: Leonhard
Thanks for the question! Yes, we can get the different sized torso and hipbelt for you. It would be considered a "special order" and only takes a few extra days to ship. All you need to do is give us a call or hop onto our Live Chat to place the order. Let the customer service rep know that you are purchasing a custom pack. Tell them the exact sizes you need and then we will order it from Sierra Designs for you. It actually is a very simple process because Sierra Designs ships right to you. I hope this helps!
Answered by: Foxxy Cleopatra
Date published: 2018-05-16

How do I know what size to get? I'm 5'8" and 140 #s

Asked by: Jake1
Hiya Jake1, thanks for your question! It depends on your torso size. Size S/M fits a 16 - 19 inch torso and M/L fits a 18 - 21 inch torso. If you do not know your torso size, follow these directions to get the measurements: 1. Tilt your head forward and feel for the bony bump where the slope of your shoulders meets your neck. This is your 7th cervical (or C7) vertebra—and the top of your torso length. 2. On each side of your body, slide your hands down the ribcage to the top of your hip bones (aka the iliac crest). With index fingers pointing forward and thumbs pointing backward, draw an imaginary line between your thumbs. This spot on your lumbar is the bottom of your torso measurement. 3. Stand up straight and have a friend measure (you'll need a flexible measuring tape) the distance between the C7 and the imaginary line between your thumbs. That’s your torso length. Hope this helps!
Answered by: Alice in Wanderland
Date published: 2018-02-19

will a bearikade weekender (650cc) bear canister fit horizontally in the sierra designs flexcapictor 40-60l pack

Asked by: sjffisher
Hiya sjffisher, thanks for your question! We don't have the bear canister in stock at our warehouse at the moment so I can't test it... but according to the folks at Sierra Designs, it should fit. Hope this helps!
Answered by: Alice in Wanderland
Date published: 2018-05-16

Do gusset straps hold the pack volume/shape at the in-between sizes i.e. 45L, 55L etc? or is it just 40L and 60L?

Asked by: Jay1
Hey there Jay1, This pack is designed to hold between 40 and 60L of volume. The gusset straps hold the pack's shape for any volume in between 40-60L. Hope this helps!
Answered by: Rocko Gigsby
Date published: 2017-08-23

Is this the updated 2017 version?

Asked by: hikinghooligan
Thanks for the question! Yes, this is the Spring 2017 version - which is the most recent.
Answered by: Foxxy Cleopatra
Date published: 2017-08-28

Does this pack have an internal water bladder pouch?

Asked by: Gungho Glenn
Hiya Gungho Glenn, thanks for your question! The hydration reservoir (bladder) is not included with the pack but it is compatible with just about any brand 3 liter reservoir. The hydration sleeve is a pocket in the pack that the bladder fits into. Hope this helps!
Answered by: Alice in Wanderland
Date published: 2017-08-03
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- + Size Guide

Size Guide Coming Soon

Please contact customer service for immediate assistance