Plug-in Blue Line Intrusion Detectors provide instant response to humans, yet eliminate most false alarms caused by animals, insects, or drafts. Compensate for temperature variations. Easy-to-mount, 2-piece design includes base with knockouts and front cover. No height adjustments are necessary for rooms where ceilings are between 7 and 9 ft. Removable terminal strip provides access to screw terminals and space for wiring. Choose from a variety of styles, each of which covers an area 35 by 35 ft. Optional monochrome and color cameras also available.