Model Number: MV-16S. Key Specifications/Special Features: With siren: 16WPower source: UM-2 x 8 piecsePower duration: approximately six hoursMicrophone: dynamicDimensions:Horn diameter: 230mmTotal length: 360mmWeight (without battery): 1.6kg Specifications: MP-5 MV-10S MV-16S MV-20S Effective distance 400yards 600yards 800yards 1,000 yards Power source SUN-3x8piecse UM-2 x 6piecse UM-2 x 8piecse UM-2 x 8piecse Power duration approximately six hours approximately six hours approximately six hours approximately six hours Microphone dynamic Mic dynamic Mic dynamic Mic dynamic Mic Horn diameter 195mm 200mm 230mm 230mm Total length 320mm 340mm 360mm 380mm Weight 1.0kg 1.5kg 1.6kg 1.65kg