xts3000 3 position concentric switch?

[nh7cy]

hello, when i first move to san francisco 4 years ago i remember first taking a look at their radios (800mhz xts3000 model I's). correct me if im wrong but i remember seeing a few with a 3 position concentric switch. i wasnt really familiar with moto radios back then so i had no idea what they were used for at first (the concentric switch, not the radio) though now i came to recognize the regular secure (crossed out circle), and the clear (circle) labels, but there was a third one which was basically a filled in circle. maybe i just wasnt paying that much attention to them but its basically what i saw.

if anybody else knows of or has seen these than what version of radios were these?

[nh7cy]

ps. a friend of mine who worked on the system said that they had different versions of the radios awhile back but had to send them back to the big M before recieving the radios that they use now. maybe somebody knows something about this?