Hi @smlevron. The battery life of your Contact Sensor will vary depending on the signal strength of the Contact Sensor as well as the level of activity the Contact Sensors experiences. If it is far away from the Base Station or Range Extender, and it’s a door that is opened/closed frequently, battery life with be shortened. If this Contact Sensor seems to be falling offline frequently, I would call our support team to have them take a closer look. With your security being our utmost priority, we want to make sure your system is running at full capacity. Please give our support team a call at one of the numbers available here. We’re taking additional steps to protect our team and help reduce the spread of COVID-19, so this has resulted in longer than normal wait times. If you are outside of the US, please read our response to COVID-19 here to see how to contact support.