The invention provides a shoulder strap, a device for carrying, and a buoyancy compensator or stabilizer. The object of the invention is an improvement to the shoulder straps of devices for carrying loads, particularly on the back of a user, the shoulder straps having a side widening portion (118, 118') towards the sternal area of the user and an arched shape, the dimensions and shapes being madeso that in worn condition the side widening portion is intended to rest on the thorax area below the cervicothoracic imaginary line and above the breast, while the section extending downward beyondtheside widening portions overlaps the side area of the thorax, the breast being positioned in the area next to a concave side edge (119) that bypasses the breast itself. In particular, the invention relates to a buoyancy compensator (100) for diving comprising equipped with the shoulder straps.