When you assign a high level to the module pin, the electro magnet can suck magnetically conductive objects. Otherwise, it will release the object.

An electro magnet is a type of magnet in which the magnetic field is produced by electric current. An electric current flowing in a wire creates a magnetic field around the wire, due to the Ampere Law. To focus the magnetic field on an electro magnet, the wire is wound into a coil with many twists of wire side by side. The Magnetic Field of All Twists of the Wire passes through the Coil Center, creating a Strong Magnetic Field there.

It's Easy to Use to Learn the Electro Magnet Principle.

DC-DC converter waterproof. With input between 16 and 36VDC for 9V and up to 5A of output current.

Wireless Switch - Remote Control - Zigbee

The Xiaomi Aqara Wireless Mini Switch is a wireless switch with just one button, which serves to control other smart devices through its Zigbee wireless connection. You can use it as a buzzer, remote control etc ... through the mobile phone application. Imagine touching a button and turning off all appliances in the house wherever you are from the App? Now with this Xiaomi button this action and many others are possible. It is compatible with different intelligent control sensors.

Mini Peristaltic Pump with 6Vdc 5W, the Velleman.