1). Electric resistance: 4ohm
2). Speaker: External diameter 45MM, dual magnet, inner magnet 4Ω 3W with FM fuction, could plug inTFcard
3). Output power: RMS 3W THD=10%
4). Audio power: 90Hz
5). SNR: ≥ 70dB
6). Power source output: DC 5V-1A
7). Charging time: 3-8hs(3-5hs to charge by charger, 7-8hs to charge by USB to computer)
8). Working voltage: DC 3.7V
9). Battery capacity: 2800mA
10). AEP Nondestructive processing
11). Dimensions: 37*37*140mm