The ACR Hot Shot(TM) Signal Mirror is designed to provide optimum sighting spot and comes with a float and whistle. The second surface mirror is telescope quality for a bright, focused image. The buoyant float is bright yellow for easy location and the whistle meets USCG standards for audible alerting in low visibility conditions. Size: 4.25&';&'; x 2.75&';&'; x.19&';&';. Weight: 1.8 oz. Includes float and whistle Provides optimum sighting spot Telescope quality second surface for a bright, focused image Whistle meets U.S. Coast Guard standards.