DM74S258 - (DM74S257 / DM74S258) TRI-STATE QUAD 1 OF 2 DATA SELECTORS / MULTIPLEXERS
National Semiconductor (now Texas Instruments)
Download the DM74S258 datasheet PDF.
This datasheet also includes the DM74S257 variant, as both parts are published together in a single manufacturer document.
Note: The manufacturer provides a single datasheet file (DM74S257_NationalSemiconductor.pdf) that lists specifications for multiple related part numbers.