Features: 1) Adopts self-designed DSP chip with patented frequency adjustment calculation technology 2) Dual quadruple PIR + MW + intelligence 3) Precision lens, enabled sensitivity of far and near objects are the same 4) German imported dual optical filter system for use indoors and outdoors with reliable function against false alarms 5) Remarkable function of pet immunity below 30kg 6) K-band detector technology, resistant to false alarms 7) For use indoors and outdoors