Amazon.com: OWC SSD Upgrade Kit for 2011 21.5-inch iMacs, Mercury Electra 250GB 6G SSD, 18" SATA III 6Gbps Data Cable, Installation Tools and iMac Screen Adhesive Tape Set : Electronics
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How To Upgrade/Replace Mid-2011 iMac 21.5" Hard Drive To an SSD! - YouTube
Opened up 2012 21.5 iMac for SSD upgrade. | MacRumors Forums
Apple iMac 2015 (mid) 21.5-inch SSD & macOS X Upgrades - ZD Laptop Service Centre
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