Check the listing for details. XFINITY Security 2.4 GHZ Wireless Digital Pet Immune PIR Motion Detector Mp-841. Color: White, Condition: New. Listed at 11.57 USD. The XFINITY Security 2.4 GHz Wireless Digital Pet Immune PIR Motion Detector MP-841 is a white, indoor-only sensor that uses batteries for power. It is designed specifically for pets, with features that include digital connectivity via ZigBee and Wi-Fi. As part of a home surveillance system, this motion detector provides security and peace of mind for pet owners who want to monitor their home remotely. Its compatibility with Xfinity systems ensures seamless integration into existing security setups.