Abstract: A signalling device suitable for being secured people and/or objects to be spotted at a distance, comprising a casing (1), anchoring means (3) suitable for constraining the casing (1) to a person's limb or an object in touch with a person, an inflatable body member (4) located in the casing (1) in a collapsed condition and having an inflation mouth (6), a cable (12) having one end thereof secured to the inflatable body member (4) and its other end anchored to the casing (1), a compressed fluid container (7) arranged to supply a fluid lighter than the air, valve means (9) in a closed condition designed to control fluid flow from the fluid container (7) to the inflation mouth (6), and control means (10, 11) arranged to open the valve means (9), thereby inflating the inflatable body member (4) and causing it to rise from the casing into the air while being anchored through the cable (12) to the casing (1) to constitute a spotting signal.