Window-Door-Alarm-Uni-Com-65463-p-The-Uni-Com-Window-amp-Door-Alarm-has-a-compact-design-that-can-be-quickly-&-simply-attached-to-windows-&-doors-It-is-ideal-for-helping-to-protect-your-home-but-can-be-alternatively-used-as-a-safety-device-on-kitchen-&-medicine-cupboards-The-loud-90-d BA-siren-is-activated-when-the-window-or-door-is-opened-&-the-magnetic-contact-becomes-separated-from-the-control-unit-p-p-Requires-3-x-LR44-batteries-supplied-p-Uni-Com-65463-Window-Doo