Swann Wi-Fi Window/Door Alert Sensor. Easy Installation (Permanent or Temporary), Wi-Fi Connected, Battery Powered, Get Alerts to Your Smartphone & control using the Swann Security App : Amazon.co.uk: DIY & Tools
Swann Window & Door Sensor 2-Pack | SWIFI-WDOORPK2-GL | ao.com
Swann One Window and Door Sensor Swo-wds1pa for sale online | eBay
Swann Wi-Fi Window/Door Alert Sensor. Easy Installation (Permanent or Temporary), Wi-Fi Connected, Battery Powered, Get Alerts to Your Smartphone & control using the Swann Security App : Amazon.co.uk: DIY & Tools