Small in size and light in weight, the ER-520W megaphone can be easily carried by a single hand. It can also provide a whistle tone. The newly developed polyimide diaphragm is employed to ensure high sound quality. Rated Output: 6 W RMS (maximum 10 W). Whistle Signal Sound. Power Source: R6P (AA) × 8 (12 V DC). Battery Life: 10 hours (30 minutes with signal). Approx. 250 m Audible Range (City areas) (30 minutes with singal). Dimensions: 160 x 256 x 260 mm. Weight: 650 g. Finish: red ABS.