Unit didn’t work due to poor ATT signal strength. No mention of or check of signal strength when purchasing unit from salesman. No obvious mention of ATT on AARP ad. Had to return as it was useless. Obtained a different cellular based system and it connected immediately. Would strongly suggest that sales staff try to determine if ATT signal strength is adequate before selling. Will give high marks to tech person that diagnosed problem. He was very nice and very thorough. Now hoping that there will be no hassles getting a full refund. Return label was received and unit sent back.