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  • Make it easy for kids to stay hydrated with water bottle pockets that are quick to access while wearing the pack
  • Large main zippered compartment; zippered front pocket; front stuff pocket is great for a light jacket; zippered internal pocket stores essentials securely
  • Side compression straps stabilize the load for a balanced hike
  • Padded hipbelt with pockets is perfect for storing snacks and treasures
  • Compatible with a hydration reservoir (sold separately)
  • Padded shoulder straps are comfortable and a padded back panel with built-in airflow channel improves ventilation
  • Zipper pulls and lash loops double as reflective accents, improving nighttime visibility


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Best Use Hiking
Bag Style Backpack
Frame Type Frameless
Gear Capacity (L) 18
Weight 17 ounces
Material(s) Nylon
Pack Access Top
Hipbelt Yes
Gender Kids'
Rated 5 out of 5 by from Excellent Daypack for Children I bought the Tarn 18 a couple of years ago for my 8 year old daughter going on her first Girl Scout hike. We hiked six miles in the rain and the Tarn performed exceptionally. It makes an excellent daypack and at 10 years of age she is still using it for when she goes geocaching or hiking. As LovetheSeattleRain observed, this isn't a Jansport book bag. I don't think the pack is so much small as it was purchased for the wrong use. This is a daypack - it can hold everything your child needs to be self-sufficient and comfortable. Although the current version looks to be cosmetically different from the one I purchased a few years ago, I would not hesitate to buy another one.
Date published: 2016-08-18
Rated 5 out of 5 by from Wish I had an Adult version Bought this for our 6 year old daughter for her forest school. She is outside almost all the time there and needs to carry a lunch, full change of clothes, water bottle, and snack. This holds all that with plenty of room for gloves, rain gear, etc. This is NOT a school bag. It will not hold a ton of books/binders. It is a camping/hiking bag and works very well for that. It has not shown any wear as of yet and have been using it for a couple months daily. We also daisy chained some shock cord on the front for extra stashing.
Date published: 2016-10-30
Rated 5 out of 5 by from Great pack!! I bought this for my 7 year old to use on our day hikes and short backpacking trips. It has been a great pack for her! It fits her very well and seems to distribute the weight on her hips properly. She never complains even when we have it loaded down with water bladder, clothes, her crazy creek hex 2 chair and some other small items. She can unzip and use the hip belt pockets easily. She can also reach the side pockets when she is using a water bottle but it took a little bit of practice to learn where to reach for it but now she can with ease. I added a rainbow bungee on the front so she can easily stash her hat or jacket if she needs to!
Date published: 2017-03-12
Rated 5 out of 5 by from Superb pack for smaller adults Do not pass this "kids" pack by if you are a smaller adult and looking for a day pack. I'm only 4'10" and this is a pack that fits me perfectly! It's well designed and accommodates everything that I might need for my average hike or snowshoeing adventure.
Date published: 2017-01-11
Rated 5 out of 5 by from Great for hiking Bought two of these for my 6 and 7 year olds. Worked great for our hike. Plenty of room for them to carry their own gear with no complaints about weight.
Date published: 2016-11-20
Rated 4 out of 5 by from Great pack for kids Hydration packs for kids are very expensive, so I was happy to see this nice, kid-sized pack that my 5 y.o. liked has a hydration bladder pocket, hanging hook, and opening for a hose. Nice organizational pockets-- not too many-- and side pockets with a strap that helps hold a water bottle in.
Date published: 2016-11-07
Rated 5 out of 5 by from Good pack for kids (bladder sold separately) I was looking for a pack for my 11 year old, who has a small frame and most packs tend to run too large. This was a good mix of small dimensions with ample storage, a stuff pouch for a jacket, and an integrated belt. The belt was important as I added a water bladder and the belt helps minimize the weight. The pack is setup to hold a hydration bladder, but does not come with one. Quality of material and stitching was good.
Date published: 2017-03-27
Rated 3 out of 5 by from Small Backpack This seems like a really well-made pack and has a lot of pockets to keep things organized (the internal visual checklist for what to take backpacking is a nice touch). Sadly, it is VERY small. The back panel measures roughly 9.5 X 15.25 inches. It is smaller than the standard Jansport backpack we were hoping to replace. It would be helpful to have dimensions in the product description. I may recommend it for a younger child, but it won't fit our 7-year-old's lunch bag and school gear.
Date published: 2016-08-10
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What are the overall dimensions, torso length, & waist size? 

Asked by: ljpeet
Approximate dimensions of the Tarn 18 are 16" x 10" x 6". The torso length is 12.5" and the waist belt adjusts from 21" to 37"
Answered by: REIservice
Date published: 2017-04-02

What size hydration bladder fits in this pack?

Asked by: MOM44
We recommend a 2L reservoir for the Tarn 18 Pack.
Answered by: REIservice
Date published: 2017-03-20

What can fit in the hip belt pockets and/or how large is it?

Asked by: Nomad001
​The hipbelt pockets on this pack measure 5 x 3.25 inches.
Answered by: REIservice
Date published: 2017-01-05

Will it be too small for a petite adult 5 ft tall?

Asked by: Peg L
This backpack is too small for most adults. However, you can compare your measurements to the pack's measurements to check if this will fit you. The torso length is approximately 12.5" and the waist belt adjusts from 21" to 37".
Answered by: REIservice
Date published: 2017-01-28

My son needs a daypack that is 1600-2200 cu. inches. Is this within that range?

Asked by: SamRaider
The pack has a gear capacity of approximately 1,100 cubic inches. A pack that has a 25 to 35 liter gear capacity is a better choice.
Answered by: REIservice
Date published: 2017-01-10

I see that you recommend a 2L hydration bladder, but would a camelbak 1.5 L fit well also?

Asked by: CD3611
​Yes, a 1.5 liter hydration reservoir will fit inside this pack.
Answered by: REIservice
Date published: 2017-04-03

Is this bag waterproof or does it come with a rain cover?

Asked by: Nml2157
This pack has a light DWR (Durable Water Repellent) but it is not seam sealed; we do not consider this pack waterproof. It does not come with a rain cover but we recommend a 20 liter size and you can view those here;
Answered by: REIservice
Date published: 2017-03-03

Would this pack be good for a 75 pound 9 year old. Planning on taking her for a 3 day hiking/camping trip and looking for her first pack. Would you recommend a different one or size. 

Asked by: Lisa86
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