... than 80dB4, Resistance: 4 ohm5, Power supply: DC5V or USB + 5V battery parameters (machine)6, Nominal voltage: 3.7 ... , Support SD card + TF phone card + USB interface, play the music memory CARDS7, Support the sound input interface 350 MM8 ... Support temperature display10, Support mobile emergency charging11, Accessory : Audio cable ,USB cable, lanyard , lithium battery ,manual. Warranty Card.Payment:1) ...