Stick-Up Cam Wired w/optional Battery?

I'm getting ready to order two Stick-Up cams - Wired from the Ring Website. Per the FAQ on the page you can order an optional battery so that they work through power outages. However, nothing in the on-line manual mentions how to install a battery with the wired cam. I don't want to order two batteries that can't be used. Can somebody confirm if the Stick-Up Cams - Wired do support an internal battery back-up.Also, what generation would these be? I see posts about a 3rd gen; but the manuals only show 1st or 2nd gen