rechargeable battery megaphone with tf card

This product support tf cards 
specification is as belowed: 
Power source:3.7V-6V          Power output: 8 W          Recording time: 120s                         Audible range: 350m                Weight: 440g    (without battery )                    Dimension: (L)249mm*(D)150mm                Functions: Talk/Record/Play/Siren/SD card 
Battery: use 1 piece rechargeable battery or 4 pieces D battery