Rucksack Sizing

We often get asked – which back system do my participants need – 65 or 65 slimjim?  Firstly here is a quick measurement guide and some quick tips.  Then further down this page is your fitting guide.


Quick measurement guide:


65 (Regular)

  • Back torso length adjusts between 17.5 inches – 19.5 inches (44-50cm)
  • Hip belts adjust between 31 inches – 64 inches
  • B. The Endurance 75 litre rucksacks have the same back system as this.

65s (Slimjim)

  • Back torso length adjusts between 14.5 inches – 17.5 inches (37-45cm)
  • Hip belts adjust between 21 inches – 64 inches (this is for slimjims!)
  • These also have narrower shoulder yokes, for boys or girls with a slimmer build.


Quick tips:

Most schools purchase a mixture of 65 and 65 slimjim, in order to achieve a proper fit for all students.

As you can see above, the Slimjim size adjusts significantly smaller (particularly on the hips) for any slim boys or girls, however it isn’t just limited to small persons, as it also adjusts fairly large for any “average size” adult.  We would however recommend that for any large/broader framed person – the standard 65 will provide the ultimate comfort.

Find out more about the Endurance Slimjim rucksacks here!


Want to download a fitting guide for your students? Click on one of the links below: