Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: Is this a mechanical relay or an SSR? I am looking for something that will not make an audible sound when switching, and can provide very fast respons
Document: Simple and straightforward* to use. Optically isolated which is nice. *Switching relay is reverse logic ... with Vcc and GND connected, pull IN1 or IN2 low by connecting it to GND to activate the relay. Pull high to deactivate the relay. It's opposite of what I first assumed as well. For an Arduino, setting the digital pin mode as an output will pull IN1 or IN2 low until you write them high.
I bought my first relay board to hook into an Arduino to operate an old traffic light. Since then, the opportunities to automate high voltage devices with these relays keep presenting themselves.The boards are easy to operate with any 5v trigger. I've used them with Arduinos and with Insteon I/O Lincs. They work reliably and are easily able to handle most uses around the house.Highly recommend these (as well as the 4, 8, and 16 channel versions for larger projects)!
Using it with a Raspberry Pi to control garage doors. works like a champ! ill buy another one should i need a relay again.
Needed a good relay to drive a garage door. This does the trick perfectly. Plugs directly into my Arduino project and provides the 5V relay to the garage door terminals necessary.
Even if the pins were on the other side, you still couldn't stack it onto an Arduino, because the configuration does not match any of the pinouts on the Arduino. To use the unit, you will need male-female jumper wires to connect the device to the Arduino or whatever you plan to connect it to. Something like the 40P dupont cable 200mm male to female wires should do.If you want a schematic, see the question above, it has a link to a RAR file with connection info.
I have used it with a Raspberry Pi to control my garage door, and a seperate light.It works perfectly. The LED indicator is a plus.
I purchased this for projects with my Raspberry Pi and it works exactly as it is advertised. This is a great hobby add-on board for a reasonable price. I should also mention that there are tons of projects explaining how to use this device in particular with the Raspberry Pi. Google is your friend.
Perfect for controlling a battery backup system I wired it to detect when house power out it triggers 12v batery to then illuminate whole house with some low voltage lights I installed beats buying a generater n some sort of detector that would cost me alot more
Can't say much more than that. I bought the unit to use with an Arduino.The unit arrived in a small bag, no specs, no schematic, no info on how to connect it to the Arduino. The unit provides 4 pins, male, Gnd, IN 1, IN 2, Vcc. It has 3 additional pins, male, Vcc, Vcc, Gnd.
these work as expected except for the mounting holes being too close to the blue screw terminals
Answer: Its a mechanical relay that makes a click sound.