Wireless Bluetooth Mini Amplifier, Touch Screen FM Radio, AUX TF Card Function

In Wall Amplifier Bluetooth Specifications: 
● Output Power: RMS 2x25W or RMS 4x20W
SP-PW420B   2CH Speaker Output 2*25Watts  
SP-PW4420B   4CH Speaker Output 4*20Watts 
● RS485 function optional:  if you need RS485 function, please add a note in the order or talk to our customer service, if not, we will send the model not with RS485 function.
(RS485 is the terminal to connect to your smart home device host)

● Output Impedance: 4-8Ω 
● T.H.D.: 0.03% 
● Frequency Response: 20Hz-20KHz 
● Audio S/N: 98dB 
● Memory Card: up to 32G 
● Size: 86*86*11mm

In Wall Amplifier Bluetooth Instructions: 
1. Speaker: Speaker wire (200 cores). RVH2X100,RVH2X200 connect to SPK R+ SPK R-.
2. Audio output wire: Audio wire (three core shielded wire: commonly known as microphone wire). RVVP2X0.5, RVVP2X0.75 connect to OUT R +OUT L+GND. Can be connected to other amplifiers.
3. Audio input wire: Audio wire (three core shielded wire: commonly known as microphone wire). RVVP2X0.5, RVVP2X0.75 connect to AUX L+AUX R+GND.
4. Video output: Connect to GND+ATV for video output.
5. Trigger the doorbell: Connect to GND+DB to trigger the doorbell.
6. RS485 interface (optional): 485 cable, connected to 485A + 485B.
【if you need RS485 function, please add a note in the order or talk to our customer service, if not, we will send the model not with RS485 function 】
7. FM: Radio antenna
8. USB: External OTG USB, can read U disk with adapter.
9. TF card: Read TF card interface.
10. Power switch: long press for 2 seconds to turn on, long press for 2 seconds to turn off,  short press for lock screen / unlock.
11. Volume down key
12. Volume up key
13. Microphone
14. Power supply terminal: Connect AC110V-240V power supply.