Comprehensive Protection - These door and window alarms sensors provide a plan for your home security, office, or any living space. With the ability to use one window, both windows, this cost-effective solution will keep you family safe. Instant Alert Help secure doors windows of home, apartment 120 dB door/window alarm chime. Easy deafening neighbors an intruder, deter intruder. attention-grabbing is audible hundreds feet away. Compact magnetically triggered sounds when opened. Customizable Settings change from Off/Chime/Alarm setting alerts people/children are coming going you're at home. No worry about being deafening, quickly press button adjust volume as need (from 85 dB). Installation simple, wire-free design perfect homes, apartments, dorm rooms, offices Security. each powered by 4 x LR44 batteries (included). Colour:White Material:plastic Package Contents: * Alarms Only above content, other products not included. Note: Light reflection different displays may cause color item in picture little real thing. measurement allowed error +/- 1-3cm.