Abstract: A device for winding up a line around a circumference of a life-buoy includes a life-buoy body with an annular groove defined therein. This annular groove receives a line in a plurality of overlaying windings. Supports are provided around the life-buoy body, and the annular groove is positioned so that it avoids interference with the supports. A line connects adjacent supports so that a line runs around the perimeter of the life-buoy. In order to compensate for the annular groove, the life-buoy body has an increased volume to balance a loss of hydrostatic push due to the volume of the annular groove. The annular groove is continuous and located in a decentralized position around an outer circumference of the life-buoy body.