The OWC 128GB (4x32GB) DDR4 RAM kit is designed as a replacement for Synology D4RD-2666-32G and D4ER01-32G memory modules. With a total capacity of 128GB spread across 4 modules, each with a capacity of 32GB, this RAM kit offers high performance and reliability. The DDR4 SDRAM modules have a bus speed of 2666MHz and a CAS latency of 19, making them suitable for demanding computing tasks. Produced by OWC in Taiwan, these RDIMM modules provide ECC registered memory features for added error correction.