Raymarine RAY 210VHF Operation Manual page 14

7) Large speaker cavity designed to provide superior audio quality.
8) Selected channel number indicated on the LCD digital display.
9) "Quick" channel 16 or 9 key to instantly switch to emergency channel 16/9.
10) Full 25 watts RF output power to the antenna port with protective circuitry
to prevent damage to the radio if operating into a faulty antenna system.
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