Its actually the LEFT HAND Slot on an A500 which is a Zorro 1 slot!
Many Hard Drive controllers were made that plugged in there.
GVPs versions were some of the best though pricey. At lest one of GVPs models had 2 miniature Zorro slots inside. They could take an Accellerator and an AT-PC Card.
Card Cages such as the Bodega-Bay and others had a connector that attached there.
The same interface is on the RIGHT HAND side of the A1000. An A500 device plugged into the A1000's connector goes in Rear-facing-forward (or such-like).
