Key Features . Install anywhere – battery powered and; compactEasy setup - simple connection to Wi-Fi network without any need for a HubBuy one sensor or many. Use the Swann Security app to create rules and; actions to link them together.Quick response – push notifications on your phone in less than 8 seconds (depending on localWi-Fi signal strength) from event.Long battery life with readily available and; cheap AAA batteries for when you do need to replace them (Indoor Siren does not run on batteries)Complete Peace of Mind Always know what\'s happening and; be protected with this window or door alarm sensor to trigger mobile phone notifications and; optional siren (sold separately). Easy to Use If a door or window is opened disrupting the magnetic connection between the Sensor and; Receiver you can activate/deactivate remotely using the app. Perfect for Renters Do-it-yourself with ease. The sensor mounts with double-sided adhesive. No need to drill walls. Ideal for apartments and; rental properties. More than an Alarm Combine with an add-on Indoor Siren (sold separately) for audible alerts to know if there’s activity even if your phone’s not handy. Build Your Own Security Connect on the Swann Security app and; add additional Swann Wi-Fi sensors siren cameras and; accessories to fit any home apartment or business for complete security. What\'s in the Box . Window/Door Alert Sensor x 2Adhesive Mounting Sticker x 2AAA Battery x 4Quick Start Guide. .