Serial Port Group Name

I am trying to have a regular user access the serial ports listed in the image.

Despite adding the user to the 'dialout' group, the user is unable to access the serial ports.

Why does the serial devices get listed under a group name such as "P4621-UNIX-dialout" and not just 'dialout'?

I changed the group names for the devices using the chgrp command, and the user was able to access the devices. But, I would like to know why it created them with the other group name in the first place.

Thanks!