The Cobra Handheld Remote Speaker Mic puts the audio and microphone of your handheld VHF in easy reach. The loud speaker is controlled by the radios volume control. Having it closer to the ear means you will hear your important radio transmissions easier. Compact Design, Screw In Audio Connector, Rotating Spring Loaded Clip, Quality Construction, Earpiece Output Jack. This unit is compatible with Cobra VHF radios and most Cobra and other Two-Way radios with a single-pin audio connector. The tip is machined to maintain the waterproof seal on Cobra Submersible VHF radios.