They ll hear you at the far ends of the field when you use the 40W thousand-foot megaphone. Easy to hold easy to carry it has more than enough range. The microphone is built into the rear end of the unit and is activated by a trigger control. Be heard up to 800 feet away with this super-powerful 40 watts megaphone. Amplify your voice cord-free and with clarity with this lightweight device. Unit includes adjustable volume control built-in siren and wrist strap for added safty. Requires 6 D batteries (not included). Powers Up to 40 Watts 1000 Yard Range Used By U.S. Army Schools And More For Indoor/Outdoor Use Variable Volume Control Tough Housing Built-In Siren Uses 6 X D Batteries Not Included Dimensions: Diameter 8 X Length 13 1/8 Weight: 2.20 Lbs Sold as : Unit