Middle of the line in price yet high in recording quality, the TRX-20 is the best choice for those of you who only want to record from one phone in particular. The TRX-20 telephone recording control is for recording the conversation only on the phone it is connected to. When used with a multi-line phone, it will record whichever line you are talking on. A modular connector simply plugs between handset cord and the telephone, and an 1/8th inch jack plugs into your tape recorder or into a sound card on your computer.  (Telephone or tape deck are not included, I have had very good results going into a standard tape deck or DAT machine.)