KY-021 Mini Reed Switch Module – Magnetic Sensor for Arduino

KY-021 mini reed switch module designed to detect magnetic fields using a compact sealed reed contact.
Provides a digital output signal when a magnet is present, making it suitable for simple on/off magnetic detection.
Small and lightweight design allows easy integration into Arduino, ESP32, and other microcontroller projects.
Ideal for applications such as door sensors, position detection, security systems, and proximity switching.