5.0V, 4k x 4, CMOS, Asynchronous, static ram From old datasheet system CMOS static ram 16K (4K x 4-BIT) 4K x 4 STANDARD Sram, 35 ns, PDIP20 CMOS static ram 16K (4K x 4-BIT) 4K x 4 STANDARD Sram, 35 ns, PDSO20 CMOS static ram 16K (4K x 4-BIT) 4K x 4 STANDARD Sram, 25 ns, CQCC20