Audio-Technica Wireless Microphones and Transmitters (ATWT1001) The Audio-Technica atw-t1001 system 10 digital unpack body-pack transmitter is a digital high-fidelity wireless transmitter designed to provide performing musicians and presenters with advanced 24-bit operation, easy setup and clear, natural sound quality. Operating in the 2.4 GHz range, far from TV and DTV interference, this digital transmitter offers easy operation. It also offers an easy-to-read digital ID display. The system 10 wireless transmitter ensures clear Communications by providing 3 levels of diversity assurance: frequency, time and space. Frequency diversity sends the signal on 2 dynamically allocated frequencies for interference-free communication. Time diversity sends the signal in multiple time slots to maximize immunity to Multipath interference. Finally, space diversity uses 2 antennas on the transmitter and receiver (sold separately) to maximize signal integrity. The versatile atw-t1001 unpack Body pack transmitter has both a high-impedance input for instruments and a low-impedance input with bias connection for use with dynamic and electret condenser microphones. Features: digital 24-bit/ 48 kHz wireless operation for high-quality sound and dependable performance 2.4 GHz range - completely FREE from TV interference three levels of diversity assurance: frequency, time and space power/mute/battery indicator shows operation status and lets you know when batteries are low, dead or installed incorrectly permanently-attached transmitter antenna transmitter pairing switch and system ID display for pairing a transmitter with a receiver high-impedance input for instruments and low-impedance input with bias connection for microphones microphone/instrument level control with included screwdriver for adjusting the input level power/mute button allows toggling between muted and unmuted operation via a single touch Audio-Technica microphones and cables are available (sold separately), pre-terminated with a unpack input connector specifications: operating frequency: 2.4 GHz ISM band dynamic range: &gt; 109 dB (a-weighted), typical total harmonic distortion:  7 hours (alkaline) operating temperature range: 32 to 104Deg.F (0 to 40Deg.C) dimensions (W x H x D): 2.76 x 4.21 x 0.98" (70.10 x 106.93 x 24.89mm) weight: without batteries: 3.5oz (99.22G)