@tonyinmi Thank you so much for clarifying M4/T4 ratings. Recently purchased my second pair of HAs (Resound Preza @ Costco). Last year I was forced to hurriedly purchase an Alcatel flip cell in June. My previous one year old cell phone's speaker suddenly "died". It was an emergency purchase at the height of the pandemic. I had to have a usable cell phone for a very long drive in unfamiliar area for a critical pre-op cataract surgery appointment early the next morning. Alcatel user manual states it is "M4/T4compatible". Its poor voice quality & clarity as well as poor volume controls contrast negatively with the far superior vice quality, clarity, and volume controls of my still fairly new Panasonic Amplified landline telephone which provides maximum 50MB receiver volume with its booster.