Technical Pro 20W Portable Megaphone Bullhorn White Blue 300M Range Siren The Tpro TPMPH20 Megaphone Bullhorn is compact powerful and portable. With each iteration of flagship megaphones weve improved the battery life power and ergonomics. This model has 20 watts of power so your voice will reach over 400 yards away! Features includes built-in button activated siren alarm function convenient folding hand grip with a durable design trusted and used by U.S. Armed forces. Battery powered and requires 4 x C batteries (not included). Works great indoors or outdoors.