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Testing the Outdoor Vitals CS40 Ultra Backpack in the Tetons | Photo Connor Burkesmith Mountain Weekly News
Backcountry & Travel Bag Reviews: Tested in the Tetons

Outdoor Vitals CS40 Ultra Backpack Review

Connor Burkesmith
November 10, 2024 4 Mins Read
467 Views
0 Comments

Outdoor Vitals has recently come on my radar within the last year or so. I’ve been thoroughly impressed with everything I’ve tried, so I was excited to test out the Outdoor Vitals CS40 Ultra Backpack. This backpack was insanely light, crazy durable and quite comfortable.

Trail Map
1 Ultralight Frame
2 Ultraweave Material
3 Design
4 Specs
5 Pros & Cons
6 Verdict

Ultralight Frame

Man Backpacking with Fall Colors and Leaves
Author and Gear Tester Connor Burkesmith Wearing the Outdoor Vitals CS40 Pack Backpacking | Photo Miranda De Moraes Mountain Weekly News

You know what sounds awesome? An ultralight backpack that functions and feels like a standard back country pack. This is exactly what Outdoor Vitals has done with their legendary 2 oz frame. In order to save weight, many ultralight backpacks are frameless. This may feel fine for the first few miles but after hours of packing it quickly becomes apparent the weight just doesn’t sit right and your back pays the price.

The CS40 Ultra Backpack uses ultralight carbon fiber frame stays to distribute the load. This results in an ultralight pack with the functionality and weight distribution of a ordinary, heavier pack. Don’t sacrifice, get the best of both worlds with the CS40 Ultra Backpack.

Backpackers wanting more capacity for longer trips should compare this pack against the Outdoor Vitals Shadowlight 60L.

Ultraweave Material

Durable Backpacking Backpack
Outdoor Vitals Used Durable Material in this Ultralight Backpack | Photo Connor Burkesmith Mountain Weekly News

The CS40 Ultra Backpack is constructed from Ultraweave fabric which is as light DCF (a comparable ultralight fabric) yet 6 times more abrasion resistant and twice as strong. The fabric is also fully waterproof. I could not be more excited about the durability of this fabric. We all know packs take a beating on the trail and having a durable pack is essential. The waterproof fabric is also great for early morning condensation and light rain.

Note: while the fabric is fully waterproof the seams are not weather sealed.

Design

Hiking with Snacks in Hip Belt
The Hip Belt Pocket Allows for Quick and Easy Access to Snacks While on the Trail | Photo Miranda De Moraes Mountain Weekly News

The overall design of this pack is wonderful. For me, 40L is the perfect amount of space for anything from day trips to multiday overnights. I have, however, been forced to master the art of light packing and understand that others may prefer more room. The main compartment is spacious, and the roll-top closure keeps gear secure and dry, though a few more internal organization options could be nice. The water bottle holders and outside mesh pocket is great.

Comfort-wise, the shoulder straps and hip belts are nicely padded and breathable, which is rare for a pack with this weight.

Specs

  • Weight – Size M, 27 oz
  • Capacity – Size M, main compartment 40 L
  • Frame – Yes, carbon fiber frame
  • Close Type – Roll top

Pros & Cons

Pros:

  • Ultralight and Durable: The CS40 Ultra Backpack boasts an impressive combination of lightness and durability thanks to the Ultraweave fabric and ultralight carbon fiber frame. This allows for comfortable carrying even on long hikes without sacrificing strength.

  • Comfortable Design: The pack features well-padded and breathable shoulder straps and hip belt, providing a comfortable fit despite its lightweight construction. This is a significant advantage compared to many other ultralight backpacks.

  • Versatile Capacity: The 40L capacity is perfect for a wide range of activities, from day trips to multi-day overnights.

Cons:

  • Limited Internal Organization: While the main compartment is spacious, the pack lacks extensive internal organization options. This may be a drawback for users who prefer more compartmentalized packing.

  • Unsealed Seams: Although the fabric is waterproof, the seams are not weather sealed, meaning the pack may not be fully waterproof in heavy rain.

Verdict

Man Wearing Outdoor Vitals Backpack While Backpacking
Connor Burkesmith Putting in Some Distance While Wearing the CS40 Backpack from Outdoor Vitals | Photo Miranda De Moraes Mountain Weekly News

Overall, the CS40 Ultra is a fantastic backpack constructed from top of the line materials with true backpacking enthusiasts in mind. I doubt you can find a lighter more functional backpack on the market.

Inventory currently unavailable at our partner retailers.

Related TETON Tested Backpacking Backpacks

  • Mystery Ranch Ravine 50L Backpack Review
  • Hyperlite Mountain Gear Porter 3400 55L Backpack Review
  • Outdoor Vitals Shadowlight 60L Backpack Review
  • Six Moon Designs Swift X 38L Backpack Review
  • Mountainsmith Zerk 40L Backpack Review
  • Forclaz Trek 100 Easyfit 50L Backpack Review
  • Mystery Ranch T100 100L Backpack Review
  • Deuter Kids Climber Pack Review
  • MaxGear Darkstar 32L Camping Backpack Review
Follow Me Written By

Connor Burkesmith

Connor Burkesmith is an independent outdoor gear tester for Mountain Weekly News, specializing in field-testing and reviewing Backcountry & Travel Bag Reviews: Tested in the Tetons, Teton-Tested: Ski & Snowboard Goggle Reviews, and Rugged Automotive Gear & Overlanding Reviews in the backcountry.

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