Note: This appears to be an earlier version of the card, using an RLL drive?
Full length Zorro II SCSI-II card. The card is fully autoconfigurable and supports autobooting. There is also enought space on the card to mount a hard drive. The card also has an external SCSI connector (probably a DB25). The card relies on the CPU to do all the I/O. The switch is probably to disable autobooting.
Thanks to Ilkka Prussi, Elmar Bauman and Sebastian Kinner.