Now reduced to $25 firm MACMEMORY 8GB Dual Channel Kit 2x 4GB 204pin 1.35v DDR3-1867 SO-DIMM 1867/14900S (1867MHz, CL13) for Apple iMac 275K (Late 2015) (4GB 2 Modules) As fitted in original specification. 2x 4GB can be combined with your original storage for a maximum of 4x 8GB capacity No issues with this memory, I have upgraded to 4x8GB