Many Osprey packs are available in multiple sizes to fit a range of torso lengths. To determine your torso measurement, please see diagram below:
This measurement starts at the iliac crest, which is the top of your hipbone on the side of your body that acts like a shelf. From this point, measure to the C7 vertebra, the knobby bone at the base of your neck when you put your head down. Reference the torso length below to match the correct pack size.