What does this weird key on my laptop do?

[GamerMan101]

Hello all! I recently acquired a Panasonic Toughbook CF-45 from a friend.
I was using it and it ran fine for its age, albeit with an annoying trackball. (kinda fun though!)
What I need help with, is with this strange key. I have never seen it on any of my customers' computers, nor any of mine, until now.

it's the F8 key, with that weird spigot icon! What does it do, and is it useful? If it is a function, should I enable it?

Also, I didn't have access to my Toughbook as of this writing, (not at home right now) so I found a pic online of the keyboard.
Thanks for the help!

 

[elbert]

Yes if you hold the Fn key in the lower left plus the F8 it disables or enables windows 95/98 power management. Not sure it will work if you have a new OS on the machine. Basically this was an old work around for power managment affecting serial port communication for modems or ISDN terminal adapters.
http/

 

[reedo_43]

ftp/ftp.panasonic.com/pub/panasonic/drivers/notebooks/Cfm34/Cfm34/34m1oso1.pdf

Page 4. Toggle power saving mode