This is the Texas Instruments SN74LS04 hex inverter IC from the 74LS family. This is part of a range of low power Schottky devices offering the same speed as standard TTL but at a fifth of the power consumption.

• 7404 base number
• 4.75 to 5.25V supply voltage
• 10ns propagation delay
• 0.4W power
• 14-DIP
• Operating temperature -20°C to +75°C