I was attempting to subscribe to the Smoke & CO Professional Monitoring plan. Reading this webpage from the Ring website I was under the impression that if I purchased a Ring Smoke and CO Listener I could subscribe https://ring.com/support/articles/u969z/24-7-smoke-co-monitoring?srsltid=AfmBOoqfPUkEoKVycAKCenDzOqhInEZ2x8YAGXsdjEI8zn756mwcXDTx The annual rate is $50.

Copied from the website: 

To subscribe to Smoke & CO Professional Monitoring, you need one or more of the following:

• A Kidde Smart Smoke Alarm orSmart Smoke and CO Alarm device
• A Ring Alarm system with a Ring Alarm Smoke & CO Listener

• • A compatible First Alert Smoke & CO detector paired with a Ring Alarm systemSo I actually purchased two of the Ring Alarm Smoke & CO Listeners and the Ring Base Station and installed them. I could never find a way to subscribe to this plan online so I called today. I was told that I could NOT subscribe because I don't have the Kidde Smart Smoke Alarm. Nowhere does it say that I MUST have that alarm. But I spoke to 2 customer service people there and was told by both that I must have that Kidde alarm so I cannot subscribe to the Smoke & CO Monitoring Plan. Needless to say, I am disappointed and having already installed the listeners onto my ceiling, I do not feel right in returning them to Amazon and I have needlessly purchased the base station. A waste of a lot of money.