Description: Sonoff Dw2 Rf Door Window Sensor App Notification Alerts For Smart Home Security Alarm Works With Sonoff Rf Bridge Note: In Order To Achieve The Dw2-Rf Using, The Sonoff Bridge Is Required.If You Have Any Questions, Please Consult Our Customer Service. Doors And Windows As The Entrances And Exits Are The Weakest Points Of Your Home. An Unsecured Door Or Window Is Like An Obvious “welcome” Sign, To A Burglar, So Door/Window Sensors Are Also Known As “entry Sensor”. As One Of The Most Popular Home Security Devices, Dw2-Rf Wireless Door/Window Sensor Is Enough Smart To Get You To Know Whether Your Door Or Window Is Open, And It Can Not Only Send You Alert Notifications, But Also Make You Know When The Entrance Point Is Opened, Making Sure Your Home Is Safe. More Importantly, The Sensor Allows You To Add A Security Camera Or Old Smartphone To View Who Is Entering Your Home, Providing You With More Details And Notes About The Uninvited Guest. Can Sync The Opening And Closing Status Of Door/Window To App Which Gives You A Peace Of Mind When You're Not At Home. History Records Check Can Be Traced Back To The Last 3 Months And This Can Help You Look Back And Check The Condition Of Your Home At That Time. Lights Are Triggered In The Action. You Can Set The Linkage In The Smart Scene Of The Ewelink App To Connect The Sensor And Your Light So That You Can Open Or Close The Door To Trigger The Hallway Light On And Off. The Sonoff Bridge Is Required For Making This Linkage Possible.This “device Sharing” Feature Is For Letting More Of Your Family Know Your Home Is Secure. After Sharing The Sensor, All Of The Shared Users Will Receive The Alert About The Condition When Someone Opens The Door. The Sensor Is 3m Adhesive Installed, Easy To Move And Remove. It Can Work Just Fine Upside Down And Sideways, As Long As The Magnet Is Less Than 5mm From The Sensor, Which Makes No Difference How The Sensor Is Located. It’s Battery Operated And Has A Low Power Consumption That Ensures The Battery Life Can Last Up 2 Years.