Features: Dual side anti-masking detection - Active IR detection, fast 20 seconds detection designed for outdoor detecting sprayed liquids and blocking items up to 25 cm (10 in.) Pet Immunity capability, up to 40 kg (90 lb) 4 dual element sensors arrangement High efficiency long focal point (1.77 in.) LoDiff lens Combination optics - mirror and Fresnel Lens for optimal sharp detection Wireless frequency selection NV780MR support two internally selectable frequencies Single or Dual operation modes Optical and digital range adjustments Dual LED and buzzer indicators Wall-mount, with built-in level tool