AC-DC Converter 110V 220V to 5V 2A Voltage Regulator Switching Power Supply

PC817 2-Channel Voltage Converter Module Optocoupler Isolation Driving Module

3.5mm Audio Out Switch Switching Board Audio Socket Signal Switching Module

2-way 2-Channel Audio Sound Source Switching Board Signal input Non-co-grounded

Preamplifier 3-Way Stereo Audio Source Switching Board Audio Signal Switcher

Stereo Audio Signal Mixer Board Mix 2way 4way Input 1way Output DC 5V-12V

Audio Signal Switch Input RCA 4 Ways Audio source Signal Relay Switching

4-way RCA Audio Input Signal Selector Switching Rotary switching for Amplifiers