The MOC303XM and MOC304XM devices consist of a GaAs infrared emitting diode optically coupled to a monolithic silicon detector performing the function of a zero voltage crossing bilateral triac driver

They are designed for use with a triac in the interface of logic systems to equipment powered from 115 VAC lines, such as teletypewriters, CRTs, solid−state relays, industrial controls, printers, motors, solenoids and consumer appliances, etc.

Features:

• Simplifies Logic Control of 115 VAC Power
• Zero Voltage Crossing to Minimize Conducted and Radiated Line Noise
• dv/dt of 2000 V/s Typical, 1000 V/s Guaranteed
• Peak Blocking Voltage
• 250 V, MOC306xM
• 400 V, MOC304xM
• Safety and Regulatory Approvals
• UL1577, 4,170 VACRMS for 1 Minute
• DIN EN/IEC60747−5−5
• These are Pb−Free Devices

Package: PDIP-6 

Link to datasheet: https://www.onsemi.com/pdf/datasheet/moc3043m-d.pdf