MightyGoods > Sierra Designs > Sierra Designs Flex Capacitor

Sierra Designs Flex Capacitor Reviews Summary and Buyer's Guide

Last updated July 3, 2019

based on 13 reviews

We have checked a few reviews and found 11 reasons to buy the Flex Capacitor - and 2 reasons NOT to buy it.

Check all the pros and cons here.

100% of the reviewers give the Sierra Designs Flex Capacitor a good or excellent rating!

Excellent (75%)
Good (25%)
Average (0%)
Poor (0%)
Bad (0%)


Reviews Summary

Here's what the reviewers think about the Sierra Designs Flex Capacitor:

Reviewers like these things about the Sierra Designs Flex Capacitor

  • Testers found out that the Sierra Designs Flex backpack is durable due to its nylon material.
  • Other testers pointed out that its volume could be expandable.
  • Reviewers noted that its the volume of its side pockets are adjustable.
  • Users also said that it includes a zippered stash pocket on its lid.
  • Other reviewers thought that its main compartment could be accessed through a single top zipper.
  • They also indicated that the bag consists of two waist belt pockets for added storage.
  • According to some users, the pack has a top-loading and minimalist design.
  • Other users found that it is easy and comfortable to carry.
  • According to those who used it, its rigid but lightweight frame makes it possible to carry heavy loads.
  • Many users pointed out that it has an exceptional back ventilation.
  • Testers noted that the bag was specific side pockets for water bottles.

Reviewers don't like these things

  • A tester thought that it was difficult to store wet items outside the main compartment.
  • A reviewer mentioned that its shoulder straps do not have external attachment points.


Crowdsourced specs across all Sierra Designs Flex Capacitor models and sizes:

Weight iconWeight2.8 oz (1.3 kg)
Length iconLength10 in (25 cm)
Width30 in (76 cm)
Height13 in (33 cm)

The bag is recommended for these activities:


Feature Summary

Many sources mention these Sierra Designs Flex Capacitor features:
  • Hydration bladder
  • Hydration compatible

Actual features depends on the model, so check the features before you buy.


vs Sierra Designs Bags

The Sierra Designs Flex Capacitor ranks #1 compared with the other Sierra Designs bags.

1Sierra Designs Flex Capacitor
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2Sierra Designs Ministry
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3Sierra Designs Revival
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vs All Bags

The Sierra Designs Flex Capacitor ranks #151 compared with all the bags we have checked.

Top 10% bag

149Burton Riders
Burton Riders
150Sierra Designs Flex Capacitor
Sierra Designs Flex Capacitor
151Yeti Hopper
Yeti Hopper
152Camelbak Aventura
Camelbak Aventura
153Lowepro Ridgeline
Lowepro Ridgeline

Selected Reviews

The Big Outside

For ultralighters or any backpacker seeking a sack with capacity versatility and a low weight, at a good price, the Sierra Designs Flex Capacitor 40-60 deserves a close look.

Posted 3 August 2017 by Michael Lanza - Read full review

PMags people


The Sierra Designs Flex Capacitor is a pack for those who don’t need, want or can’t have a whole quiver of packs… but does need at least a damn good one.

Posted 4 October 2016 by Paul Mags - Read full review

Gear Junkie

Overall, this is a well designed, functional, light backpack that can carry significant weight if needed. It will provide a versatile solution for hikers and others who want a backpack for many uses on high mountains and trails anywhere you may roam.

Posted 25 August 2016 by Sean McCoy - Read full review

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Bag ID 33350. Images from Amazon Product Advertising API and shop datafeeds.

Last updated on July 03, 2019