Texas Instruments TravelMate 4000M - Microphone;Headphone Kit

Microphone/Headphone Kit
The TravelMate 4000M has an optional microphone and
headphone kit (TI Part No. 9793399-0001). The kit also
comes with installation instructions. To plug in your
microphone, insert the plug into the Mic connector on the
back of the notebook.
Microphone/headphone connections
Microphone/Headphone Kit
11-12 TravelMate Options