CMSA64GX4M4A2666C18 DDR4, 2666MHz 64GB 4x16GB Apple SODIMM, Unbuffered, 18-18-18-43 Optimal Performance on Mac CORSAIR Mac Memory is specifically engineered and rigorously lab-tested at high stress levels and temperatures to guarantee compatibility and optimal performance on Mac systems Increase Productivity Today’s applications demand large amounts of high-performance memory to run at peak efficiency. Save time and increase your productivity by improving your system’s performance with extra memory, so you spend less time rendering and buffering – and more time working or playing. Limited Lifetime Warranty Backed by a limited lifetime warranty for your complete peace of mind, with CORSAIR’s world-class customer support ready to assist you 24/7 by phone or online. COMPATIBILITY iMac 5K Display (Mid-2017) Fan Included No Memory Series Apple SODIMM Memory Type DDR4 Memory Size 64GB Kit (4 x 16GB) Tested Latency 18-18-18-43 Tested Voltage 1.2V Tested Speed 2666MHz SPD Latency 18-18-18-43 SPD Speed 2666MHz SPD Voltage 1.2V Speed Rating PC4-21300 (2666MHz) Compatibility iMac 5K Display (Mid-2017) Package Memory Format DIMM Package Memory Pin 288