Osprey Packs Stratos 36 Backpack

Sizing Chart

Osprey Packs Sizing Chart

Step 1 - Pack Sizing

All Osprey packs, save the transit bags, are available in multiple sizes to fit a range of torso lengths. To find your torso length, have a friend measure your back along the spine from the level of your iliac crest (the top of your hipbones) to your C7 (the knobby bone at the base of your neck).

Step 2 - Hipbelt Sizing

To determine your hipbelt size measure around your hips, not your waist. A properly fitted hipbelt rides centered over the hipbones and needs to be very snug; after all it will be carrying the bulk of the pack's weight. The padded portion should wrap well around your hips, leaving a gap of 3 to 6 inches between the tips of the pads when securely tightened.

ErgoPull

Nearly all Osprey hipbelts use an exclusive ErgoPull design. It creates mechanical advantage to provide extra leverage in cinching down the hipbelt. The ErgoPull design also draws tension along the top and bottom of the belt, not through the center, so it distributes pressure more evenly over the padding and relieves direct pressure on the hipbones.

Step 3 - Harness

Osprey Crescent & Luna, Aether & Ariel and Waypoint packs offer interchangeable shoulder harnesses. Harness sizing usually corresponds to pack size, but your best bet is to try one on. A properly fit harness should terminate 2 to 3" beneath the armpit. Webbing should not touch the body. By breaking the hook and loop connection and sliding the harness up and down the backpanel the torso length can be adjusted up to 3". (see illustration).

Step 4 - Overall Fit

Once you have the correct size pack, harness and hipbelt, and the torso length set properly, it's time to put some weight in the pack (20 to 30 pounds of well distributed weight will do) and dial in the fit. First, snug down the hipbelt and harness. Connect the sternum strap (A) - position it about 2 inches below your collarbones and snug it down lightly. Finally, tighten the load lifter straps to draw the load solidly against your back. The lift straps (B) should come off your shoulders at a 45 to 60 degree angle in Osprey's ReCurve and Ethereal Suspension packs. In other models these straps serve more as compression straps and ride flatter; they may even angle downwards.

In a good fit, there should be no pressure points and no gaps between your body and the pack. With Osprey's ReCurve packs, final tweaking may involve custom fitting the aluminum stays to your back.