Riedel TAC-E1R XLR4F - in-ear headset (listen-talk combination) for applications in high noise environments, microphone with noise cancellation, flexible clip-on microphone boom, frequency range listener: 200 - 5000 Hz, impedance listener: 780/1450 Ohms, max SPL listener: 100 dB, frequency range microphone: 20 - 20000 Hz, impedance microphone: < 2. 2 Ohms, microphone characteristic: omnidirectional, microphone type: electret, right version; weight: 53 g, color: black, optimized for use with Bolero intercom system