This DTMF (Dual-Tone Multi-Frequency) microphone has a direct entry keypad. Keypad numbers are used to dial a phone number, while three buttons (A, B, C) below the keypad can be programmed to conveniently activate select radio features.

Operation is simple: press and hold down the Push-to-Talk (PTT) button; release it to listen. Hold the microphone 1 to 2 inches from your mouth, and speak clearly into it.