1,MH‑M38 is a low‑power BT design solution, supports the latest BT 4.2 transmission, two‑channel stereo lossless playback. 2,After the module is connected to BT, it can quickly realize BT wireless transmission, which is very convenient. 3,Long connection distance, BT connection distance up to 20 meters in an open environment. 4,Support USB sound card, plug and play, connect the module to the computer with a USB cable, and the music can be output through the module's amplifier. 5,Can be directly powered by the MICRO USB cable 5V, or it can be connected to a 5V power supply or a 3.7V lithium battery. Item Type: Digital Amplifier Board 5V: The Positive Pole of the Power Supply is 5V GND: Negative Pole of Power Supply VBAT: Lithium Battery Anode 3.7-4.2V Land or L-: Left Channel Output (Directly Connected to the Speaker) Rand or R-: Right Channel Output (Directly Connected to the Speaker) Audio Output: Output Left and Right Channel Stereo Audio Signals, Which Can Be Connected to Two 2-8 Ohm and 3-5W Speakers Respectively, and 4 Ohm 5W Speakers Are Recommended for Storage. 1 x Digital Amplifier Board 2 x Terminal 2 x Wire Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.