A device, operated by an electric current, and causing by its operation abrupt changes in an electrical circuit (making or breaking the circuit, changing of the circuit connections, or variation in the circuit characteristics).
"Thank you so much for the outstanding work you did transferring my cassette tape to CD's. You did an excellent job! I am especially pleased with how clearly I can hear my Dad's voice. As I mentioned when I placed this order my Dad has passed away; so you can imagine how precious this recording is to me now. I also want to thank you for ..."
