Limiting values of operating conditions, applicable to any device of specified type as defined in its published data.
"I just wish to say that I'm very impressed with the high quality of work you produced in converting my ancient cassette tape ("Joy" by Apollo 100) to CD. The quality, in my opinion, was better than the condition the tape offered! I just wish to say your restoration techniques are terrific (nearly miraculous). Thanks for saving a bit of music I ..."