Visonic K9-85 SMA Next Plus Pet-Tolerant Digital Pir Detector 15m (50 ft) 90 degree multiple-curtain coverage with creep zone Pet-tolerant for animals up to 38 kg (85 lb), Enhanced false alarm immunity by combined Fresnel and cylindrical optics Long-term stability and reliability thanks to advanced true digital FM processing, Industry's best catch performance based on proprietary Target Specific Imaging and 3D cylindrical optics Ultimate false alarm immunity based on patented True Motion Recognition with exceptionally high sampling rates and "Event Verification" algorithm Remote walk-test capabilities, Solid-state relay for silent trouble-free operation Fast and easy adjustment-free installation, Attractive sleek design suitable for any home or office environment