The HC-12 433MHz Transceiver is a wireless communication Module, which is based on the RF SI4463 chip, has a built-in microcontroller and can be configured by AT commands, the maximum output power is 100mW (20dBm) and the receiver sensitivity differs from: 117dBm to -100dBm, depending on the transmission speed. Accepts 3.2V - 5.5V and can be used with 3.3V and 5V UART voltage devices.

This is the FeatherWing Adalogger: it adds a real-time clock with battery and micro SD card storage to any Feather mainboard. Using the Headers, you can connect a FeatherWing to the top of your board and let the board fly!

NodeMcu consists of open source firmware and a development kit that helps to prototype your IoT (Intemet of Things) project through some lines of Lua language. The NodeMcu has integrated ESP-12 serial WiFi with GPIO, PWM, ADC, I2C and 1-WIRE capabilities, integrates USB-TTL serial with super reliable industrial strength CH340 for superior stability on all supported platforms.

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.

The DUALR3 takes your home to the next level. The DUALR3  is a built-in Switch WiFi Dual Relay Module that installs behind any standard switch for turns it into a smart switch for wireless remote control with mobile devices or voice command. Unify your appliances into an integrated wireless network to make them communicate with each other, which is convenient to control, including lights, appliances and motorized installations like shutters, awning, etc.

Doors and windows that can be used as entrances and exits are the weakest points in the security of your home. An unprotected door or window is like an obvious "Welcome" sign for a thief, so the Sensors of Door/Window are also known as the "Entry Sensor" . As one of the most popular home security devices, the Sensor of Door and DW2-RF Wireless Window is smart enough to know if your door or window is open and you can not only send alert notifications, but also notify you when the entry point is opened, ensuring the security of your home.

The MINIR2, like the MINI's rugged Diy Two-Way Smart Switch, has been redesigned to bring safety and performance to an optimum level. The small and compact smart switch is used for different types of switch boxes, even the smallest standard EU switch box. Convenient to automate your appliances in the eWeLink app with your mobile phone or by voice command.

Development Board ESP32-DEVKITC-S1.

The Bluetooth Module 4.0 BLE Micro EVB can be easily placed on your PCB card, just ignore problems such as "how to design an antenna", "how to make a bluetooth chip work" and so on. The Bluetooth 4.0 BLE Micro EVB Module is perfect for portable projects. With it, you can use Android or IOS devices to communicate with your clothes!

ITDB031 is a serial port BLE Module. It is based on TI's CC2541 BLE chip. With it, you can transfer data wirelessly and do remote control. It supports central and peripheral modes. And it supports remote control for the other side that is connected. You can also support custom commands when you combine it with other devices. BLE Bee is compatible with XBee. You can simply connect it to XBee.

Note: The serial interface is 3.3V, not the typical 5V, as with many Arduino boards.

This small, rugged and powerful card features Wi-Fi and Bluetooth connectivity that, combined with its low power architecture, makes it a practical and economical solution for your connected projects.