Part Number: HMA851U6CJR6N. 8GB DDR4 Matching Kit (2x 4GB) - SK Hynix PC4-2666V. OEM Reliability: SK Hynix is a premium manufacturer for Dell, HP, and Lenovo. Dual-Channel Ready: Using two 4GB sticks instead of one 8GB stick allows your processor to access data faster, improving overall system responsiveness.