Sizing Chart

PACKS - For Both Men and Women


Because they have a long range of back length adjustments, The Daylites and Ultralites (day to mid-volume packs) i.e. Marathon & Mountain Magic, Flow-Mo Friend, Liquid Agility and Mobile Intention have one back length. These models also have sewn in hipbelts in one size to fit all body sizes.

All larger models of Ultralites and all the Stronglites come in two back lengths, Short and Long. To determine which size is best, you need to determine your back length: Measure the distance from the top of your hip bones to the mid- point of your shoulder (where the shoulder strap goes over the shoulder) to determine your back length.

For accuracy, stand with your back against a wall with a hard covered book and pencil in hand. Place the book vertically against your side with the bottom edge of the book resting on top of your hipbone and the back edge against the wall. Mark the height of the lower edge of the book on the wall. This is the height of the top of your hips.

Now place the book vertically by the side of your head, with the back edge resting against the wall and the bottom edge resting on the mid-point of one shoulder (half way between your neck and the end of your shoulder - this is where the center of the shoulder straps should lie). Mark the height of the bottom edge of the book on the wall. This is the height of your shoulders.
Now measure the difference in height between the 2 marks on the wall - this is your back length.  

  • If your back length is less than 15” (38 cm), choose the short: S
  • If your back length is greater than 15” (38 cm), choose the long: L

WHAT IS MY HIPBELT SIZE, Small, Medium or Large?

Our large models with Pelvic-Form Hipbelts come in 3 hipbelt sizes. The medium size, M is standard. To decide whether this will fit, use a tape measure to determine your waist size, as the top of the hip belt goes around your waist.

If this distance is less than 33.5” (85cm) choose the S size, if it is greater than 37.5 ” (95 cm), choose the L size.


For Cool People:  One size fits all

For Cool Pups: 

7" - 11" neck = Small

11" - 14" neck = Medium

14" - 17" neck = Large

22" - 26" neck = X Large