ICD provided several quality products to the Atari community over the years. This board was created to allow upto 3 different OSs to be individually selected prior to boot. They used it to great effect to promote two modified OSs they licensed called OmniViewXL and OmniMonXL. OmniViewXL is a software-based 80 by 24 character display compatible with several word-processing programs common at the time. OmniMonXL is a modified version of the original XL operating system giving you an enhanced floating-point subroutine and a resident machine language monitor.
My clone of the board is as faithful as I can make it. That means it is subject to the same limitations as the original.