RTS BP-325 Dual-Channel Binaural Programmable Beltpack for Dynamic Microphones - BlackThe BP 325 is a portable beltpack for use with RTS Two Wire intercom systems. The BP 325 is a binaural (stereo) programmable two channel beltpack with program input capability. The BP 325 is for use with a dynamic microphone only. The BP 319 is a microprocessor controlled one channel intercom where the BP 351 is a microprocessor controlled two channel select intercom beltpack. The BP 319 and BP 351 have connections for headset earset microphones