 Introducing the Geo-MD Wireless Encrypted Motion Detector for the Geo Alarm. Pet immunity up to 55 pounds, a 90 degree detection angle, 32.8 feet of detection length, wireless and encrypted utilizing the 433 MHz frequency. With tamper and low battery monitoring, pin settings controlling sensitivity and pet immunity, 5 years of battery life, 32 degrees to 122 degrees Fahrenheit operating temperature, 2.16 by 2.99 by 1.65 inches, make sure that this device is discreet. Once again, ladies and gentlemen, introducing the Geo-MD Wireless Encrypted Motion Detector for the Geo Alarm.