2 Wire Magnetic Reed Switch
Reed switches are used to monitor the opening and closing of windows or doors (or essentially anything that opens or closes). There are two parts to a reed switch... one has a magnet inside, the other a reed switch (which is triggered when the magnet comes close and deactivates when the magnet is pulled away). When wired (DIY with 2 low voltage wires) to a smart home binary sensor input device, you can easily monitor and create automations for doors and windows. Can be mounted with double-sided tape or screws.
