Descriptions:Switch Type: NC(normal closed type), the circuit is closed normally, and, that if a magnet not near it, the circuit open. It consists of a pair of contacts on ferrous metal reed in a hermetically sealed glass envelope. There are two types of reed switches: normally open reed switches and normally closed reed switches. In the presence of a magnetic field, the contacts of a normally-open reed switch will close. A normally-closed reed switch is closed when it is not near a magnet; as a magnet is brought close to it, a normally-closed switch will open. .
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Tuya Zigbee Door Sensor for Smart Home Wireless Window Detector Remote Control Smart Life APP Alexa Home Security Alarm System
Aliexpress UK
The certification is ce. no need to worry about it falling off when you are working or doing exercise. it can also be used as a security alarm in public places, which is very suitable for people of all ages.
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Ewelink Zigbee Door Sensor Wireless Magnetic Window Open Closed Alarm Detector Works With Zigbee2MQTT Alexa Google Need Gateway
Aliexpress UK
The Door Alarm Sensor 2 Pack is a modern, white wireless device designed to detect door and window openings, making it ideal for enhancing home security, garage protection, and preventing children from leaving the house without permission. This product is easy to install with its surface mount plug profile and does not require batteries as it is powered by 2 AAA batteries (not included). The alarm emits a loud 120 dB sound when triggered, providing peace of mind knowing your property is safe and secure.
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Zigbee Door Sensor Magnetic Window Open Closed Alarm Detector Works With Ewelink APP Alexa Google Need Gateway Black White Color
Aliexpress UK
When the magnetic sensor is disconnected, the KERUI door and window alarm system will issue a loud 120dB warning to prevent theft and unnecessary access, preventing your child from sneaking out. It will alarm when the door or window is opened, and will stop alarm once you close the door or window.
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Aqara Water Leakage Sensor Water Leak Detector Sensor IP67 For Home Remote Alarm Security Sensor for Mi Home Homekit app
Aliexpress UK
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Aqara Water Leakage Sensor Water Leak Detector Sensor IP67 Smart Home Remote Alarm Security Soaking Sensor For Xiaomi mijia App
Aliexpress UK
The tamper on this unit is a sprung micro switch which will detect the removal of the cover. Tamper: micro switch. 1 X Surface Magnet. Colour: White. Material: High impact Polystyrene. Check availability with our specialists.
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TAIBOAN 433MHz Wireless Doorbell Home Music Door Bell Alarm Volume Adjustable Compatible With WiFi GSM Alarm System EU/US Plug
Aliexpress UK
Compact size alarm. Sensor type: alarm. - Magnetic sensor switch detects entry. Alarm type: sound. Test the setup by switching on the system of the main unit and see whether the alarm can be triggered by opening the door/windows.
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Video Doorbell S330 + Entry Sensor Video Doorbell S330: Easily see who's at your door and guard your packages with one integrated device. Entry Sensor: If a forced entry is detected, a siren as loud as a jackhammer will be triggered on HomeBase, and...
eufy
WIFI Tuya APP. It support IOS and Android APP. Siren output <500mA. if alarm occurs, the alarm host will dial preset number and play the record voice. WIFI Standard IEEE 802.11b/g/n Wireless Standard.
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Ewelink Zigbee3.0 Water Sensor Alarm Water Leak Detector Flood Alert Overflow Security Alarm System Works With Zigbee Gateway
Aliexpress UK