And the switch and magnet are separated, and the switch is open. Switching Pressure: 100VDC. Close = short circuit = create a path for the current. 10 Pair Door Window Sensor. Switch Output: NC (Normally Closed).
eBay
Awapow Refrigerator Alarm Wireless Door And Window Delay Induction Alarm Security Anti-theft System Smart Home Magnetic Sensors
Aliexpress UK
Wireless PIR Motion Detector. Support 100 Wireless Detector and 4 Wired Detector. Tuya Wifi GSM alarm system. Support GSM SIM Card and 2.4G Wifi Network. 2 x PIR Detector. Solar Wireless Alarm System Siren.
eBay
KERUI W181 Alarm System Secutrity Home WIFI GSM Alarm Tuya Smart Motion Detector Door Sensor Burglar IP Camera Work Alexa Google
Aliexpress UK
External wired alarm connectors: 1 channel external wireless siren, 1 channel. Siren output：<500mA. GSM system：850/900/1800/1900MHz. Support the alarm such as battery problem, low power battery anti-pry alarm etc.
eBay
1-3pcs ZigBee Door Sensor Smart Home Window Entry Detector Smart Home Alarm System Voice Control Magnetic Security Sensor
Aliexpress UK
Tuya Wifi GSM alarm system. Support 100 Wireless Detector and 4 Wired Detector. Support GSM SIM Card and 2.4G Wifi Network. Solar Wireless Alarm System Siren. You can add more than 100 wireless detectors and 4 Wired Detector.
eBay
Elecpow Door Window Alarm Home Security Wireless Burglar Alarm Door Magnetic Sensor 120dB Anti-theft Alarm For Home Kids Safety
Aliexpress UK
Sound index: 120dB. At 120dbs, this siren will not only alert the neighbors of the intrusion, but scare away the burglar right out of your house! This piercing, plug-in siren can be plugged into your keypad/Console.
eBay
Home Security Burglar Alarm Wireless Door Opening Alarm Anti Theft Intruder Enter House Magnetic Sensor Door Window Entry Alarm
Aliexpress UK
eBay
KERUI Wireless 433MHz Window Door Magnet Sensor Detector For KR-W181 W184 W204 Home Security Alarm Systems Burglar Anti-theft
Aliexpress UK
SCARE BURGLAR AWAY When someone trigger this system that will be alarm to scare thief away and also will make a phone or sending a message to someone which you save the phone number on the main unit BUILT-IN BATTERY This system work well when someone cut wires or power off. You don’t worry other people intrude your house when power off REMOTE CONTROL You can control this gsm alarm system Arm/Disarm/Voice Monitoring /Intercom by cellphone anywhere EMERGENCY HELP You can press an alarm button on the remote control when some emergency thing happen, this system will go off right now and will make a phone CELLPHONE FUNCTION This main unit can make the phones like a cellphone so this also is a spare mobile phone
eBay
HEIMAN Zigbee 3.0 Fire alarm Smoke detector Smart Home system 2.4GHz High sensitivity Safety prevention Sensor Free Shipping
Aliexpress UK
And the switch and magnet are separated, and the switch is open. Switching Pressure: 100VDC. Close = short circuit = create a path for the current. 10 Pair Door Window Sensor. Switch Output: NC (Normally Closed).
eBay
Tuya WiFi or Zigbee Door Sensor Smart Life Home Security Door Open Alert Sensor Window Sensor Alarm System with Black Color
Aliexpress UK