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Sizing Guide for Kids Packs

Measurements for packs are based on the length of the back. Have your child stand up straight with their hand on their waist and bend their head forward. Measure from the C7 vertebrae (the one that sticks out a bit when the head is tilted forward) to roughly where their pants waistband is (you ideally want this to line up with their illiac crest (top of the pelvic arch) but the waistband should be close.


If the measurement is close to the next size, round up and get the larger pack.


Be sure to select the correct size, the ages listed are for estimates only, sizing is based on the length of the child’s back. Please see our sizing info with questions.


Specifications (Small):

Dimensions: 12” H X 9” W X 3.5” D (30.5cm X 23cm X 9cm)
Weight: 14 oz (397gm)
Age range approx 2-4 years, 10”-12” back


Specifications (Medium):

Dimensions: 14” H X 9” W X 3.5” D (35.5cm X 23cm X 9cm)
Weight: 15 oz (425gm)
Age range approx 3-6 years, 12”-13” back


Specifications (Medium):

Dimensions: 16” H X 9” W X 3.5” D (40.5cm X 23cm X 9cm)
Weight: 16 oz (454gm)
Age range approx 5-8 years, 14”-15” back