The new ultra small Honeywell-5800PIR-RES is wireless motion detector is pet immune selectable up to 80 pounds. It is a passive infrared with a 35'x40' coverage area. Works with all Honeywell systems that use the 5800 series wireless.

Range: 35 x 40 ft.
Battery Type: 3 volt lithium
Battery Life: Up to 5 years
Operating Temp: 14 to 131 degrees F
Size: 3.5" Tall x 2.5" Wide x 1.5" Deep (Super small compared to most others!)