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Amazon.com: CANADUINO 4 Relay Module 10A / 250V Opto-Isolated Inputs 3-24V for Arduino etc. : Electronics
ELEGOO 4 Channel DC 5V Relay Module with Optocoupler Compatible with Arduino UNO R3 MEGA 2560 DSP ARM PIC AVR STM32 Raspberry Pi : Electronics - Amazon.com
JBtek 4 Channel DC 5V Relay Module for Arduino Raspberry Pi DSP AVR PIC ARM : Electronics - Amazon.com
Amazon.com: SunFounder 2 Channel DC 5V Relay Module with Optocoupler Low Level Trigger Expansion Board Compatible with Arduino R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 Raspberry Pi : Electronics
Amazon.com: AITRIP 4 Channel 5V Solid State Relay Module Board High Level Trigger Compatible with Uno Duemilanove MEGA2560 MEGA1280 ARM DSP PIC : Industrial & Scientific
SainSmart 5V 2A 4 Channel Solid State Relay Module High Level Trigger Black for Arduino Uno Duemilanove MEGA2560 MEGA1280 ARM DSP PIC: Amazon.com: Industrial & Scientific
Amazon.com: HiLetgo 5V 4 Channel Relay Shield for UNO R3 Relay Shield Four Channel Relay Shield for UNO R3 : Automotive
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Excelity 4 Channel DC 5V Relay Module for DSP AVR PIC ARM DIY Development Controller - - Amazon.com
Amazon.com: AC100V-250V 30A High Power 2-Channel Relay High Current DC5V High-Low Level Trigger Switch Module for Arduino : Electronics
Amazon.com: ELEGOO 4 Channel DC 5V Relay Module with Optocoupler Compatible with Arduino UNO R3 MEGA 2560 DSP ARM PIC AVR STM32 Raspberry Pi : Electronics
Amazon.com: Electronics-Salon 2 DPDT Signal Relay Module Board, DC 12V Version, for Arduino Raspberry-Pi 8051 PIC. : Electronics
Amazon.com: ELEGOO 4 Channel DC 5V Relay Module with Optocoupler Compatible with Arduino UNO R3 MEGA 2560 DSP ARM PIC AVR STM32 Raspberry Pi : Electronics
Amazon.com: HiLetgo 12V 4 Channel Relay Module with OPTO-Isolated Support High and Low Level Trigger : Industrial & Scientific
Amazon.com: Electronics-Salon 4 DPDT Signal Relay Module Board, DC 12V Version, for Arduino Raspberry-Pi 8051 PIC. : Electronics
Amazon.com: 4 Channel I2C Electromagnetic Relay Module Compatible with Arduino, Raspberry and MCU 3.3V 5.0V iot : Electronics
Amazon.com: Solid State Relay SSR Board for Arduino Uno Yun Leonardo Zero : Electronics
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Amazon.com: YWBL-WH 30A 4 Channel Relay Module Expansion Board with Optocoupler for Arduino Raspberry Pi DSP AVR PIC ARM (5VDC) : Electronics
Amazon.com: Electronics-Salon 4 DPDT Signal Relay Module Board, DC 12V Version, for Arduino Raspberry-Pi 8051 PIC. : Electronics
NOYITO 4-Channel 12V Computer USB Control Switch Relay Module Drive-Free Relay Module Plug and Play Suitable for PC Smart Controller: Amazon.com: Industrial & Scientific