ADDON COMPUTER MEMORY MODULE 4GB DDR4-2666MHZ R UDIMM KITAddOn 4GB DDR4 SDRAM Memory Module 4 GB (1 x 4 GB) DDR4 2666 PC4 21300 DDR4 SDRAM CL17 1. 20 V Non ECC Unbuffered 288 pin DIMM VPN: AA2666D4SR8N 4G SKU: RSC941132 UPC: 821456039907 DIMM 4 GB of memory to heighten your computer's performance 2666 MHz of memory speed skillfully manages the variety of apps and computational tasks DDR4 2666 PC4 21300 interface synchronizes electrical and clock signals for an efficient data transfer rate