Burglar Intruder Anti-theft Door Window Loud Wireless Magnetic Alarm Sensor. FEATURES: Easily Mounted by Adhesive Tape to Window or Door. Magnetic Sensor Switch Detects Entry Protecting Your Home or Office Whether You Are in or Out. Warning Door/window Sticker is Supplied Free in Package. Operating by 2xbatteries(not Include) HOW TO USE: Open the Battery Cover,Match Positive and Negative Signs and Insert2 Triple A Batteries Correctly, Close the Battery Cover Fix the Main Unit Which Has On-off Switch at the Side of the Door&window. Attach the Bar Magnet to Door Frame/window Frame with the Arrow Aligning with the Reference Line of the Main Unit. Switch To"ON" Position of the Main Unit So As to Be in Alert State,it Will Give an 90bp Alarm if the Magnetic Senor Has Been Separated from the Alarm Device when Someone Opens the Door/window. Please Turn off the Switch when You Don\'t Need Remove the Batteries to Prolong the Lifetime of the Product/batteries if It Will Be Set Aside for a Long Time INCLUDES: 1 X Alarm Unit 1 X Magnetic Sensor . Your order will be shipped from abroad so please allow the necessary time of at least 14 work days for delivery due to ongoing delays in postal deliveries globally.