Please Check Compatibility.

To find specifications of your machine:

If the machine is working:

• Go to your Apple menu, select "About this Mac". You will find the serial number and year of the machine in this window.

If the machine is not working:

• Look at your logic board directly, you should see your serial number and or 4 digits EMC number on the port where the memory is seated.
• You can then enter this into the search field at theeverymac websitewhich will tell you the complete specifications on your system.
• Please contact us if you are still unsure of compatibility and we can help you to determine that if this is the right part for you.
• Model A1398 (15" Retina)
• MacBookPro10,1 Retina Mid 2012: MC975LL/A (2.3 Core i7)
  MacBookPro10,1 Retina Mid 2012: MC976LL/A (2.6 Core i7)
  MacBookPro10,1 Retina Mid 2012: MD831LL/A (2.7 Core i7)
  MacBookPro10,1 Early 2013: ME664LL/A (2.4 Core i7)
  MacBookPro10,1 Early 2013: ME665LL/A (2.7 Core i7)
  MacBookPro10,1 Early 2013: ME665LL/A (2.8 Core i7)
  MacBookPro11,2 Late 2013 (IG): ME293LL/A (2.0 Core i7)
  MacBookPro11,2 Late 2013 (IG): ME293LL/A (2.3 Core i7)
  MacBookPro11,2 Late 2013 (IG): ME293LL/A (2.6 Core i7)
  MacBookPro11,2 Mid 2014 (IG): MGXA2LL/A (2.2 Core i7)
  MacBookPro11,2 Mid 2014 (IG): MGXA2LL/A (2.5 Core i7)
  MacBookPro11,2 Mid 2014 (IG): MGXA2LL/A (2.8 Core i7)
  MacBookPro11,3 Late 2013 (DG): ME294LL/A (2.3 Core i7)
  MacBookPro11,3 Late 2013 (DG): ME294LL/A (2.6 Core i7)
  MacBookPro11,3 Mid 2014 (DG): MGXC2LL/A (2.5 Core i7)
  MacBookPro11,3 Mid 2014 (DG): MGXC2LL/A (2.8 Core i7)
  MacBookPro11,4 Mid 2015 (IG): MJLQ2LL/A (2.2 GHz Core i7)
  MacBookPro11,4 Mid 2015 (IG): MJLQ2LL/A BTO (2.5 GHz Core i7)
  MacBookPro11,4 Mid 2015 (IG): MJLQ2LL/A BTO (2.8 GHz Core i7)
  MacBookPro11,5 Mid 2015 (DG): MJLT2LL/A (2.5 GHz Core i7)
  MacBookPro11,5 Mid 2015 (DG): MJLT2LL/A BTO (2.8 GHz Core i7)