Tighten the shoulder straps: The sponge of the shoulder strap should go smoothly and snugly around the shoulder, there should be no gap between the shoulder strap and the body, check your shoulder strap connection strap, the position of the shoulder strap connection strap adjustment buckle should be higher than the highest point of the shoulder A little bit below (about above the collarbone). At the same time, a finger should be able to be inserted behind the highest point of the shoulder, otherwise, the shoulder strap will be pulled too tight.

How tight should the straps be? The strap adjustment buckle should be located one palm-width away from the armpit. If the shoulder strap adjustment buckle cannot reach the correct position, you need to put the backpack down and re-adjust the size of the carrying system of the bag (the adjustment method of various mountaineering bags is different).
Adjust the position of the chest strap: After the shoulder straps are adjusted correctly, buckle the chest strap so that it fits your body gently, the position of the chest strap is about 5 cm below the collarbone. Note that the chest strap must not be tight so that you can breathe comfortably.