Product Spec: 32GB (2 x 16GB) DDR4 2666MHz (PC4-21300) CL19 ECC SO-DIMM 1.2V Especially designed for micro-servers, workstations, networking platforms and embedded systems. Support Synology NAS 21 Series. 100% in house tested undergo rigorous quality control Strictly audited DRAM chips with top quality 10-layers of PCBs Limited Lifetime Warranty