Pyle PLBKA100BK 100 Watts Waterproof Portable Bicycle/Scooter MP3/iPod Music Player (Black) Convenient and easy portable MP3 speaker fo cycling, walking, travelling, hiking, camping, and many other outdoor activities. Charging time: USB : 7 Hours , USB(5V/1A) A/C Commercial Adaptor: 4 Hours Speaker Output : THD+N=0.1% @ 50W RMS/ 100W MAX, S/N Ratio = 96dB @ 50W RMS / 100W MAX , Speaker Frequency Response: 400-18KHz , Impedance: 8 Ohms Earphone Output: THD+N=0.5% @ 33 ohm , S/N Ratio = 95dB @ 33 ohm Built in 2G Memory Capacity