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  • Adjustable back panel and side compression straps combine to provide a customizable fit
  • Water bottle pockets feature secure snap closures and are positioned forward on the hipbelt for easy access without removing the pack
  • Removable top-lid offers customizable pack volume
  • Large mesh pocket in the front provides breathable, easy-access storage
  • Loops on the front allow ice axes, tools and more to be attached


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Best Use Backpacking
Frame Type Internal Frame
Gear Capacity (L) 40
Gear Capacity (cu. in.) 2,441
Weight 2 lbs. 10 oz.
Weight - Metric 1,191
Adjustable Torso Yes
Fits Torso 12 - 16 inches inches
Fits Waist/Hips 22 - 36 inches
Material(s) 420-denier ripstop nylon
Frame Material Spring steel
Pack Access Top loading
Number of Exterior Pockets 4 + Main
Dimensions 24 x 12 x 9
Gender Kids'
Rated 5 out of 5 by from Little Boy, Big Pack Our 9. y.o. is going to camp and must carry all his clothes, sleeping bag, roll and personal items for 14 days. Since he will be flying our external frame will not work for airline travel. We tested all the internal frame smaller packs and women's packs in this range. We were pleasantly surprised at how well this pack fit him. At first I was concerned that the strapping may be a bit too technical, but he has handled adjusting the load well. He has finally accepted packing cubes to keep this clothes organized at camp...9 y.o.s and organization skills are mutually exclusive terms. The cubes help distribute the load in the pack. We are trying to cap his carry weight at 15 pounds. The pack has flown well and handled the practice hikes well (with only 10 pounds.) Looking forward to many years of hiking with this bag!
Date published: 2017-03-29
Rated 5 out of 5 by from Great introduction pack for a child I bought this for my 9 year old son for Cub Scouts & he loves it! Says it feels like he is carrying nothing on his back. Even asked if it could be his school
Date published: 2017-05-14
Rated 2 out of 5 by from Works for petite women I am a petite woman - 5'3, 111 lbs and a 16/17'' torso length. Recently I needed a travel pack for a trip to Europe. After hours of trying on backpacks at REI, I finally bought this Tarn 40 kid's pack, not because it was the perfect pack, but because nothing else fit! Come on, backpack-makers! Small people travel and hike too! It is extremely basic. It is a 40L pack, so technically it will hold the same amount of stuff that the regular adult packs hold, but there are a few frustrating aspects to this bag. As much as I wanted a pack with a zipper, not one of them fit me. All the packs for smaller people are top-loading and have a badly designed drawstring top that cinches shut, but it is difficult and awkward to operate. This particular pack is no exception. Also, there is basically only one giant compartment to this bag. There is a small place to store flat objects inside the bag, but you could never put a laptop in this pocket. Maybe a few maps...The bag does have hip belt pockets, but the only other places for storage are two open pockets on the side for things like water bottles, and a loose pocket on the outside for slipping something like a raincoat in. The bag has nowhere to attach locks. I never would have bought this bag if other options had been available to me. But because I did not have that luxury, this one will have to do. If you are a petite woman with a shorter torso, and are having trouble finding a backpack, try this one. At least it doesn't hurt my hips and shoulders, so as far as comfort level goes, it works ok. Another benefit is that it has the ability to adjust to different torso lengths, which not all backpacks have.
Date published: 2017-05-02
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Are these packs hydration bladder compatible? If so, what size fits?

Asked by: brandonrb82
The Tarn is hydration compatible. Any size reservoir up to 3 liters/100 oz. will fit in the hydration sleeve
Answered by: REIservice
Date published: 2017-03-20

Would the Tarn 40 be capable of carrying alpine skis?

Asked by: Ranger72
We do not recommend using this pack to carry alpine skis. An actual ski pack is a better choice.
Answered by: REIservice
Date published: 2017-04-27

How do you measure your child to know if this would fit? He is 11yrs old, weighs 110 and is 4ft 10in. 

Asked by: Jason
The most important measurements to take into consideration when sizing a backpack are the torso length and waist size. REI puts these measurements in the specs tab on backpacks we sell. The link below is a great article on how to find your torso and hip size for a backpack.
Answered by: REIservice
Date published: 2017-03-30

does it come with a raincover

Asked by: bevin
This pack does not come with a rain cover. The 40 liter REI Co-op Duck's Back Rain Cover is a good choice.
Answered by: REIservice
Date published: 2017-05-08

The graystone color appears to be a gray purple color, is that the case? Or is it strictly gray.

Asked by: elenamw
​The graystone color is a shade of purple.
Answered by: REIservice
Date published: 2017-03-20

Is this pack waterproof?

Asked by: LAMntz43
​This pack is water resistant.
Answered by: REIservice
Date published: 2017-03-14

Would the Redpoint 3/4" Webbing Straps with Side-Release Buckles work with this pack as extensions to carry a sleeping bag

Asked by: Madcat2020
Yes, combining the lower loops with the daisy chains will allow you to carry a large diameter sleeping bag. The pack does come with straps that can hold a small sleeping bag, sleeping pad or tent.
Answered by: REIservice
Date published: 2017-06-12

Is this good for a 6-7 day backpacking trip?

Asked by: Backpack
This pack is not recommended for a 6 to 7 day backpacking trip. A pack with a gear capacity of 70 liters or larger is a better choice.
Answered by: REIservice
Date published: 2017-06-05
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