A-Tech 8GB (2x4GB) RAM for Apple MacBook Pro (Early/Late 2011), iMac (Mid 2010, Mid 2011, Late 2011), Mac Mini (Mid 2011) | DDR3 1333MHz PC3-10600 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
APPLE IMAC 21.5in CORE I5 2.5GHZ MID-2011 8GB 500GB SMART DVD MAC OS SIERRA (Renewed) : Amazon.co.uk: Computers & Accessories