EPROM chips, version 4.10, for 21-voice Ensoniq SD-1. In the SD-1, O.S. 4.0 and later O.S. disks will be incompatible if your EPROM firmware is lower than version 4.0. To determine the current EPROM version in your keyboard, press the Presets button, and while holding it down, press the Master button.
This part may be either NEW or USED.
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