Check the listing for details. eufy Security Entry Sensor Send Alert Triggers Siren for Doors Windows Detects. Color: White, Condition: New. Listed at 29.99 USD. eufy Security, Entry Sensor, Detects Opened and Closed Doors or Windows, Sends Alerts, Triggers Siren, 2-Year Battery Life, Indoor-use Only, Requires HomeBase, Optional 24/7 Protection Service Product Details Entry Sensor Protect Your Doors and Windows from Break-Ins with eufy Security Entry Sensor. Once a window or door is ajar by 1.5 inch, an alert will be sent to your smartphone, and a 100-decibel siren will go off on the HomeBase (can be disabled). Requires eufy Security HomeBase. eufy Security: Less Trouble. More Secure. Ever Expandable. • Surveil your home from front to back for total peace of mind • Created by the same team as Anker—renowned for exceptional quality and innovation FAQ 1.Is there any battery included in the package? Yes, a CR123A Battery is included. 2.Can I use my own router to pair with eufy Security Entry Sensor? No, you can only use eufy Security HomeBase to pair with eufy Security Entry Sensor. 3.Can I use it in an outdoor environment? No, it is designed for indoor use only (Not Weatherproof). 4.How can I know if I need to change the battery? There's low battery life notification, which will inform you when the battery level is lower than 10%. 5.How to install the entry sensor? Step 1: Peel off the mounting tape and stick or screw the sensor onto the door or window you want to monitor. Step 2: Stick the magnet part onto the frame of this door or window near the entry sensor's printed ''Magnet'' wording. Note: Please make sure the distance between entry sensor and the magnet is shorter than 1.5in. Shipping PolicyPayment PolicyReturns PolicyAbout eufy All products will be checked carefully and packed in good condition before shipping. Item will be shipped within 3 business day after the payment has been received. -- If you buy more than 3 items and your shipping address is in PUERTO RICO, Please kindly request the total invoice before making the payment or we may ask extra payment before sending your order. Because USPS charge more shipping fees for boxes to Puerto Rico. Shipping Service Delivery Time Delivery Weight Range First Class 3-7 Business Days