32GB (4 X 8GB) Kit Memory for Apple iMac Late 2015 27-inch 1867MHz DDR3 SO-DIMM (PARTS-QUICK Brand) at Amazon.com
Amazon.com: Late 2015 Apple iMac with 3.2GHz Intel Core i5 (27 inch Retina 5K, 8GB RAM, 256GB SSD) Silver (Renewed) : Electronics
A-Tech 32GB (4x8GB) RAM for Apple iMac Late 2015 27 inch Retina 5K | DDR3L 1866MHz / 1867MHz PC3L-14900 1.35V 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
OWC 8GB (2 x 4GB) 1867 MHZ DDR3 SO-DIMM PC3-14900 204 Pin CL11 Memory Upgrade (OWC1867DDR3S08S) at Amazon.com
Amazon.com: Late-2015 Apple iMac with Retina 5K/3.2 GHz Intel Core i5 (27-Inch, 8GB RAM, 1TB) (Renewed) : Electronics
Adamanta 16GB (2x8GB) Apple Memory Upgrade Compatible with Late 2015 iMac 27" Retina 5K Display DDR3/DDR3L 1867Mhz PC3L-14900 SODIMM 2Rx8 CL13 1.35v RAM DRAM at Amazon.com
A-Tech 8GB RAM for Apple iMac Late 2015 27 inch Retina 5K | DDR3L 1866MHz / 1867MHz PC3L-14900 1.35V 204-Pin SODIMM Memory Upgrade Module at Amazon.com
NEMIX RAM 16GB Kit (2x8GB Upgrade) DDR3-1600 SODIMM PC3-12800 for Apple MacBook Pro Mid 2012 / iMac Late 2012 / iMac 2013, Late 2014, Mid 2015, Mac Mini Late 2012 at Amazon.com
Timetec 16GB KIT(2x8GB) Compatible for Apple Late 2015 iMac (27-inch w/Retina 5K Display)