Megatronix - SC615 - Super Loud 12Volt 118db 15Watt Six Tone Car Alarm Siren Super loud six tone electronic siren DC 6V - 12V 118db 15Watt Dimensions: 4.25"L x 3.25"W x 3.5"H Ideal for any 12 volt system: cars, trucks, go cart, golf cart, RV, boat