The Rolls HR73 is a half-rack space digital MP3 Recorder / Player. The unit is ideal for installations where quick, easy, yet high fidelity recording is required. The MP3 format, SD card slot, and USB connection make the HR73 a powerful tool for local audio capture. Churches, schools, restaurants, etc., all benefit from the features of the HR73. Please read the manual carefully to understand the capabilities and use for this unit.