These are new old stock NEC 8k by 8bit RAM chips for SEGA master series games consoles. They have the SEGA part number 315-0298-15 and generic part number D4168C-20. These are 20ns versions which is 5ns faster than the originals. I have a large number of other SEGA master parts... please contact me for details. Date coded 1988. Discounts available for bulk buy.
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