RICH BASS: To provide rich, powerful bass, we install a Bass Vibrating Membrane at the bottom of speaker, It will vibrating up and down when the speaker working, it will produce airflow, this air flow driven bass diaphragm,to produce low frequency. HD SOUND: Used much improved integrated circuits boost maximum volume enhance up to 50%. 3 watts high-end low-impedance speakers larger than normal 5 watts. The higher and deeper voices are crystal clear without any noticeable distortion, even maximum volume. PORTABLE: Under 6.2 ounces, size: D1.89xH1.54 inches. High capacity rechargeable 700 mAh lithium battery for up to 6 hours of playtime at 2/3 volume on a full charge. And you can get a Case, with some holes, music can be released through the holes. So much better for travel and hiking, superlight and easy to fit in your backpack, baggage.