Headset Headworn Microphone for Shure QLX-D, ULX, ULX-D, SLX, BLX4R QLXD4, SLX4, BLX4R, BLX24R Wireless Microphone System Condenser Unidirectional ta4f 4 Pins Black. Output Impedance: ≤680Ω.
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