correct ram for a late 2009 iMac 21.5

Also, this Apple Support article may come in handy:

Install memory in an iMac - Apple Support

Search the App store (either iPhone or Mac) for a free app called "MacTracker". It pretty much lists every product Apple has made and you can search for your 2009 iMac 21.5" for technical details.

Image taken from MacTracker:

BDAqua wrote:

32 GB possible

Not exactly…

Great help from Jeromyk! :)👍

32 GB possible

Memory Upgrades for Apple iMac 2009 - Up to 32GB (macsales.com)

OOPS! My goodness, thanks dialabrain & my apology Tomas124.:(

You're welcome.