About iMac memory

• Capacity: 16GB-64GB
• Memory Type: 260 pin SO-DIMM
• Speed: DDR4-2400MHz (PC4-19200)
• Unbuffered
• Nonparity
• Meets Apple specifications
• JEDEC Compliant
• RoHS Compliant
• Limited lifetime warranty

How much memory is right for you?
With more memory in your iMac, you can run more apps simultaneously and work with larger data sets with a higher rate of performance. 
iMac memory
Supports up to 64GB of DDR4-2400MHz PC4-19200 SO DIMM
Upgrade Tips

• Slots: 4 (user accessible)
• interleaving Supports: Yes
• Install in pairs for best performance.