A1311 - 21.5" iMac

• Late 2009
• Mid 2010
• Mid 2011

A1312 - 27" iMac

• Late 2009 (C2D)
• Late 2009 (i Series)
• Mid 2010
• Mid 2011

A1418 - 21.5" iMac

• Late 2012 
• Early 2013
• Late 2013
• Mid 2014
• Late 2015

A1419 - 27" iMac

• Late 2012 / 2013
• Late 2014 / Mid 2015 5K

A1862 iMac Pro 27 - Late 2017

• Late 2017 3.2 GHz 8 Core
• Late 2017 3.0 GHz 10 Core
• Late 2017 2.5 GHz 14 Core
• Late 2017 2.3 GHz 18 Core
  

A2115 - 27" iMac