The Bosch Blue Line 2nd Generation Pet-Friendly Motion Detector contains two Fresnel lenses, which generate sharply-focused images of the monitoring area, allowing for enhanced early alerting of intruders. The high optical gain of Fresnel lenses provides better immunity to electronic noise, reducing the occurrence of false alarms. This Bosch detector is easy to install and features flexible mounting options facilitating optimum placement for detection. The pet-immunity mode ensures the device does not generate false alarm signals from any pets. The mode can be manually deactivated to match a user's requirements. When deactivated, the Blue Line Gen2 motion detector offers enhanced detection performance in line with the brand's non-pet friendly models. When pet immunity mode is activated, the detector differentiates between signals caused by the presence of humans and pets. It will ignore the motion of up to two pets under 45 pounds (20kg). It will also ignore the activity of multiple small rodents. If you have any questions about the Bosch ISC-BPR2-WP12, or any other products and services that we offer, please do not hesitate to get in touch with us on . We will be happy to answer any questions that you might have.