HD74S51P: Dual 2-wide 2-input AND-OR-Invert Gates
<p>High-Speed Schottky Series
</p>
Manufactured by Hitachi
<a href="//commons.wikimedia.org/wiki/User:Mister_rf" title="User:Mister rf">Mister rf</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>