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
OWC SSD DIY Kit for All Apple 27-inch iMac 2011 Models
OWC Data Doubler Optical Bay Hard Drive/SSD Mounting with tools (iMac 2009- 2011) | eBay
2011 imac 27" 32GB - final stage of 1TB + 2TB SSD upgrade (replaced HDD & optic drive). Also cleaned out the fans and case. Running 'SSD Fan Control' & 'Macs Fan
OWC Hard Drive Upgrade Kit for Apple iMac 2011
How to Install a 2.5-inch SSD in the SSD Drive Bay of a 27-inch iMac Mid 2011 (Updated) - YouTube
HOW TO] iMac 27" (mid 2011) two SSDs in RAID 0 config + HDD | Page 2 | MacRumors Forums
Further Explained: Apple's iMac 2011 Model Hard Drive 'Restrictions'