Timetec 16GB KIT(2x8GB) Compatible for Apple DDR3 1067MHz / 1066MHz PC3-8500 RAM for Mac Book (Mid 2010 13-inch), Mac Book Pro (Mid 2010 13-inch), iMac (Late 2009 27-inch), Mac Mini (Mid 2010)
16GB 2x8gB RAM Memory for Macbook Pro MacMini iMac 2009 2010 DDR3 1066 PC3 8500 | eBay
How to Upgrade Memory in a Late 2009 21.5-inch or 27-inch iMac - YouTube