This multi-functional siren controller allows you to adjust pitch and volume. In the dub and reggae scene, it's affectionately known as the "Pew Pew Machine." It's so much fun, you could play with it all day. There's no manual, but you should be able to understand it immediately from the names written on each knob. The intuitive design and directness of the knobs are top-notch. Power-on and operation have been confirmed. Excellent condition. Beautiful item. Includes a 12V power cable. This is a rare gem, as it's only made to order and rarely available.