From the Manufacturer Featuring piezo dynamic technology, USB drive, and more, the PMP58U delivers high-end performance at an affordable price Click here for a larger image Built-in USB drive lets you play pre-recorded messges and music right from your computer Thanks to its light-weight design and ergonomic handle, the PMP58U is easy to handle and even easier to use Professional Piezo Dynamic 50 Watts Megaphone With USB Function They'll hear you at the far ends of the field when you use this megaphone. Easy to hold, easy to carry, youŌĆÖll be heard up to one mile The microphone is built into the rear end of the unit and is activated by a trigger on an ergonomic pistol grip. Use this super-powerful, 50 watt megaphone indoors or outdoors. Plus, itŌĆÖs got USB playback -- just plug in a USB stick with your favorite digital music. Amplify your voice cord-free and with clarity with this lightweight device. Unit includes adjustable volume control and a built-in siren. Requires 8 x C batteries or a 9V DC power supply (both not included). In addition to standard talk mode, the PMP58U features a built-in siren so you can get everyoneŌĆÖs attention fast. Variable Volume Control Adjust the volume to your preference with the variable volume control.