Sonic the Hedgehog 3 (EPROM prototype)

This is a prototype cartridge currently owned by LocalH. There is no visual difference between this and the final release, and it is believed to contain the same ROM. The cartridge works with a retail copy of Sonic & Knuckles. There is no battery on the PCB, therefore savegames don't persist when power is turned off. Savegames do persist while the system is powered on, however. This cartridge has not been dumped yet. It was purchased from PACHUKA for approximately $100. As a side note, EPROM stands for Eraseable Programmable Read Only Memory. These chips are usually in a ceramic package with a small glass window that allows you to see the chip die. The purpose of this window is to allow erasure of the ROM by ultraviolet light so it may be reburned with other data, in this case probably a later build of Sonic 3.