Shure UA874US, Active UHF Directional Antenna, Frequency range: 470 - 698 MHz, Switchable input sensitivity: -6 dB, 0 dB, +6 dB, +12 dB, Impedance: 50 Ohm, Compatible with Shure elements that provide 10 - 15 V (DC voltage), Thread for attachment to a microphone stand, Dimensions (H x W x D): 316 x 359 x 36 mm, Weight: 0.32 kg