Mini Speaker / Super Mini Sound Box For iPod Our unique invention of "Resonant space magnification technology within the mini speaker" perfectly solves the difficult problem of the narrow resonant space in mini speaker. 1)New idea union portable mini design; 2)Patented technology: Extendable resonance; 3) rubberized finish; 4)lithium battery inside; 5)Standard 3.5mm audio plug Features: Shell materials: QIMEI ABS757 Shell Painting: UV PAINT spray HIFI I: APA3010KA or LM4871 Speake: MAGNETISM PREVENT(4ohm)36MM*2W Loudspeaker output: 2.35W Rating power: 1.85W Frequency response: 100Hz-20KHz Signal-to-Noise: More than 85dB Distortion: Less than 0.5% Polymer battery Voltage: 3.6V Polymer battery capacity: 300MAH Polymer battery charging Voltage: 4.2V add or reduce 0.05V Product net weight: 50g(including battery) Product specification: 5.2cm*3.2cm Battery Charge time: DC 5V 200MA to 300MA around 2.5 hours; USB 4 hours; Battery Discharge time: MP3 volume in 31mv, about 2 hours; MP3 volume in 20mv, around 8 hours; (in the baise of volume level. Music rhythm ect long or short of time) Package materials: Speaker 1PCS +English manual USB cable 1PCS+/audio input wire 1PCS