Amiga 1000 Phoenix Technologies 8mb external RAM expansion.
This unit is designed to attach to the A1000's zorro slot. It will electrically attach to an A500 - but not physically attach without modifcations. This particular unit has 1mb onboard, and it is assumed to be expandable to 8mb. There is a disable switch on the front. There is also a passthrough on the side - but it is female for some reason