This is a brand new vintage auto Air Raid Siren/Horn. This steel horn has a 5" Diameter and features a gray enamel powder coated finish, rugged construction, easy mounting, & detailed instructions. This wires up to any 12v source and has that distinct vintage air raid - Military siren sound. This is a great addition for 12 volt Trucks, Imports, Street Rods, as well as various projects you may be working on. Really let them know you're coming with this compact and functional Siren/Horn!