iMac Intel 21.5" EMC 2428 (Mid 2011) SD Card Slots
iMac Intel 21.5" EMC 2428 SD Board
Replace the SD card reader board and its cable in a Model A1311 Late Mid 2011 21.5" iMac.
In May 2011, Apple upgraded the 21.5" iMac. Externally, the machine features edge-to-edge glass and an aluminum rear bezel. Internally, an LED display, 4 RAM slots (to upgrade to a maximum of 16 GB RAM), more powerful video processing, and featuring quad Core i5 and i7 processors.