Detects entering person by comparing constant background temperature with rapidly changing temperature created. - Very easy Installation - Detection Coverage: Fan shaped Areaof 130°, Distance up to 10 Meters - Wall, Ceiling or DeskTopmount - Flylead supplied so that the TK2 can be connected with Door Bell Button - Selectable Alarm, Chime, Off Function - Requires 9V battery or AC Adaptor - Size: 90 x 60x 60mm - Weight: 90g