ER520S Compact Handheld Megaphone. 10 Watt Maximum Output - 8 AA batteries (8 hrs) - Range: 250m (speech) / 315m (siren) - Anti-bacterial treatment for all models (mouthpiece/microphone and handle) - High durability ABS or ASA resin construction - Compact and lightweight - Wide frequency range for enhanced audio quality - Neodymium magnets and Polyimide speaker diaphragms - Five year warranty