The RCA RP3504 Cassette Tape Recorder features RCA's classic "shoebox" design and versatile features. It has automatic level control and will automatically stop at the end of tape in play and record mode. With its easy-to-use 6 push button controls, you can record, pause, fast forward, rewind and stop/eject. Its microphone is built-in and is a condenser microphone for optimum clarity. But its also capable of recording through an external mic with its external microphone jack. Take it on the go or use it at home. It runs on both battery power (4 AAA not included) and AC/DC power.