Let's keep the car line moving", "take another lap...", "everyone back to the bus..". Schools, bus tours, sports training facilities, etc. can all use this powerful 25 watt megaphone that can be heard up to a half mile away! We really like this megaphone because it has a detachable anti-howl microphone. You can attach the mic to the back, squeeze the trigger on the handle and talk into the back of this system like a standard megaphone - OR - detach the mic, sling the megaphone over your shoulder with the included adjustable, padded strap and walk around the grounds making your voice heard! If you need to get everyone's attention, the unit has both a SIREN and a WHISTLE feature. That'll wake 'em up! Unit uses 8 "C" batteries (not included) and weighs approximately 3 1/2 lbs (without batteries).