If you figure on using this with your existing Panasonic Dect phone system then forget it. First problem is that the TH1211 acts like a base unit so you will have to drop the base unit for your existing phone and if that has an answering machine you may not want to do that. Second problem, and this is the big one, your existing handsets will not have the programming needed to control the TH1211. Pairing was no problem but that was not a consideration when we couldn't use the house phones.
Panasonic customer service told me "No problem" before I bought this - boy were they wrong. I dumped this and bought an Xlink. The Xlink works with every phone in the house DECT or hardware. You disconnect your phone company and let the Xlink feed signals to the house phone wiring.