Adamanta16GB (2x8GB) Memory Upgrade Compatible with Late 2015 iMac 27" Retina 5K Display DDR3/DDR3L 1867Mhz PC3L-14900 SODIMM 2Rx8 CL13 1.35v RAM DRAM

The memory was easy to install and an immediate improvement in performance was noted.

If you need to add more ram to your iMac 27in Retina display late 2015, look no further.

I purchased this to compliment the existing memory in my late 2015 27" Retina iMac. The two 8GB DIMMs were packaged well and very easy to install. Going by the instructions, I took out the existing DIMMs and put these new ones in their place, and then re-installed the old ones in the remaining slots. I closed up my computer, reconnected the power and other cords, turned it on, and after a minute or two was back in business.Computer responsiveness is a subjective thing and difficult to quantify, but without reservation I can say that my iMac is noticeably faster with the new memory added, now totaling 32GB. It is most evident when working with Photoshop and other memory intensive software, but can be seen in the general system and it just feels overall a speedier computer. My only regret is that I waited so long to upgrade, but the price is now affordable so it was worth it.While power users like myself are only likely to notice significant improvements in system responsiveness for certain tasks, adding RAM to your computer is NEVER a bad thing if you can afford it. These Adamanta 16GB (2x8GB) Apple Memory Upgrade DIMMs are an upgrade I should have done years ago.~ Kort

Got the product quickly and was installed by my local Guru

My Mac came with the standard 8GB RAM, so I finally purchased this set to bump it up. They are quality made, easy to install, and give me the extra memory to better handle multiple applications simultaneously. Recommended.