STANDARD HORIZON ：HX40E、HX210E、HX380、HX400IS. YAESU ：VX-6R、VX-7R、FT-270R、FT-277R. Microphone Type Stain-body Capacitor Microphone. Microphone Resistance 2.2kΩ. Speaker Resistance 8Ω. Speaker Audio Input Power 0.5W.
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