Model ; AM25DP Power Output : 20W Rated / 25W Max. Voice Range : Approx. 400m ( Siren 500m) in quiet surroundings Microphone : Unidirectional Inputs : Dedicated Microphone Dimensions : Horn Dia 230mm, Length 382mm Weight ; 1.40 kg (1.20 kg without cells) Class-D Amplifier provides extremely high efficiency of power consumption resulting in extended battery life. All ABS body, sturdy yet lightweight. Built-in Siren. Clear sound, long-range & efficient. Microphone with Volume Control & built-in recording / playback facility. Message up to 240 seconds (4 minutes) can be recorded. MP3 playback facility through USB, SD/MMC card & Aux input. Can be used as a hand-held as well as on the shoulder. Recommended to use AA Alkaline Cell or Li-ion battery for extended life and better performance.( CELL COST EXTRA )