LAMPHUS SoundAlert 100 Watt Hand-held Microphone & 5 Audio Warning Mode Electronic Air Horn/Siren Light-Control Switch Box User Manual available for download under Product Information Details Search "Lamphus 100W Siren" on YouTube for Product Video. 100 Watt amplifier. Function includes: Radio/Standby, Wail, Yelp, Hi-Lo, Horn, and Manual Siren. 2 auxiliary switches fused at 20 amp each allows other equipment to be powered on/off.; Rugged, water resistant housing; Wiring Accessories Included.