The UNIDYNE III Model 545SD is a dual-impedance, unidirectional, dynamic microphone. Shipped connected for low-impedance operation, the mic features a silent magnetic reed on/off switch. The UNIDYNE III is a favorite for instrument pickup and recording, and can be used on lecterns for public address systems such as those used in political conventions and legislatures, convention halls, hotels, public auditoriums, stadiums, schools, and churches. (545SD-LC Cable not included).