CT8G4DFS8266 is a 8GB single Ranked DDR4 desktop module that operates at speeds up to 2666 MT/s and has a CL19 latency. It is an Buffered DIMM. It conforms to the industry standard DDR4 ECC UDIMM layout of 288 pins and is compatible with systems that take DDR4 2666MT/s UDIMM memory. Micron quality – a higher level of reliability: As a brand of Micron, one of the largest memory manufacturers in the world, Crucial Desktop Memory is the standard for reliable performance. From the original SDRAM technology all the way to DDR4, we’ve engineered the memory technologies that have powered the world’s computers for 40 years and counting. When you choose crucial memory, you’re choosing memory that’s backed by a limited lifetime warranty and designed for the world’s leading systems.