... size. 2,Rechargeable polymer battery. 3,Led lighting. 4,Power 1. Product Specifications: Bluetooth Specification:V2.1+EDR Frequency Working ... Pictures showing the functions and how to use by steps. (a) Function 1, music player ( turn on it, to press and hold the button ... last for 3 seconds, it will twinkle.) Function 3, Power bank( To charge for mobile phone with 2200mah capacity) Function4, handsfree ...