3pcs Relay Module for Arduino, ESP32, ESP8266, Raspberry Pi, 1 Channel, 5V, High/Low Level Trigger

These 5V 1-channel relays have been exactly what I needed. The 3-pack gives you flexibility across multiple projects without breaking the bank. Wide compatibility!! works with Arduino, ESP32, ESP8266, Raspberry Pi, or any 5V/3.3V microcontroller. Trigger voltage range is 3.3V to 5V, so no level shifting headaches. Versatile switching: has both normally open (NO) and normally closed (NC) contacts, plus the ability to select either high-level or low-level trigger via a simple jumper. Rare to find both options on budget relays. Built-in protection: optocoupler isolation keeps your microcontroller safe when switching higher voltages. The fault-tolerant design is a nice touch too: even if the control line breaks, the relay won't accidentally activate. Solid specs: handles up to 250V AC / 10A or 30V DC / 10A. More than enough for lights, fans, and most household stuff. For three relays at this price? No brainer.

Another part for my esp32 projects. I used this to control a little door strike from esp32 via home assistant. Once you understand how to wire for open and not open options, with common, it's not too tricky and works well. I liked I got 3 incase i messed up one, or needed multiple relaying. The terminals that screw down are a plus for quick connecting and disconnecting

Nice relay set for switching. Easy to set-up and give you plenty of options. Has a single common wire with a NO and NC connection. The relay will switch when the 5v DC input signal goes high. Be careful to observe what voltages your CPU works on. This is a 5V device, some CPUs are 3.3V and don't work well with this product. I'm using these to change the 5v signal of the CPU output and turn on a 24v solenoid valve. These work great.

These supposely contain a flyback diode on the board. However, my Arduino was sometimes resetting after switching the relays off (which control some solenoids). I had to install my own own flyback diode and everything is working well. That might be unique to my situation.

Seem to work fine, but be careful if you are planning to mount them. The holes in the corners of the boards are too close to the terminals for any screw I have been able to find to fit properly. Currently they are just hanging loosely from 1 screw. Might end up clipping the corners off the boards to allow the screws just a little more room for mounting.