OWC 8 GB (2 X 4GB) ram PC8500 DDR3 1066MHz sodimm 204-pin Memory Upgrade Kit, (OWC8566DDR3S8GP), Compatible with MacBook Pro, MacBook, Mac Mini and iMac at Amazon.com
How to upgrade RAM in the (Mid 2017) 5K iMac and save up to ~$900 [Video] - 9to5Mac
Apple 24” iMac (Early 2009); iMac9,1 Installation Guides & Specifications - Macfixit Australia
8GB (4GBx2) Team High Performance Memory RAM Upgrade For iMac “Core 2 Duo” 3.06 24-Inch (Early 2009) MB420LL/A iMac 9,1. The Memory Kit comes with Life Time Warranty. in Kuwait | Whizz Memory
How to install memory for your iMac 9,1 to 12,2 DDR3 1333MHz - YouTube
iMac | 2.0 GHz Core 2 Duo | 20 Inch | Mid 2009 - Techable.com