What are the shoulder straps for in this belt — isn't a belt around the waist enough? — Rigid support for lifting weights size 2 216-2

The card does not mention shoulder straps. According to the description, the «Rigid support for lifting heavy loads» (size 2, for external use) is intended for use while lifting heavy loads and helps support the body under load; before use you need to make sure the belt is put on correctly and comfortably secured around the body. The card does not describe the material, the construction or whether there are straps or other elements — details are on the packaging.

General information (not a manufacturer's instruction): no belt replaces proper lifting technique; in case of back pain, injury or chronic back conditions, it is better to agree on the regimen of use with a doctor.