1 channel 5V Relay Module, Opto-coupler isolated, for Arduino and MCU projects.

OPTO 22 IDC5 Input Output Module

5V 16 Channel Relay Module with OPTO-Isolated High and Low Level Trigger 16 Ways

5V Relay Module 1/2/4/6/8 Channel Opto-Isolated for Arduino ESP32 Raspberry Pi

5V 8 Channel Relay Module with OPTO-Isolated High and Low Level Trigger 8 Ways

1 channel 12V Relay Module, Opto-coupler isolated, for Arduino and MCU projects.

Elko Level Switch For Monitoring 1 or 2 Levels HRH Universal Input 12-240V AC/DC

Lot of 5X OPTO 22 IDC5 AC/DC Digital Input Module AC244004DE