Standard SSM-517A Earpiece MicrophoneModel: SSM-517AThis earpiece microphone replaces the SSM-55A and works with HX890, HX870, HX400, HX407, HX380, HX290, HX210, HX40
Standard SSM-21A Speaker MicrophoneModel: SSM-21AThe SSM-21A is a high performance Submersible speaker microphone desiged especially for their hand held transceivers.
