OWC 16GB DDR4 2133MHz PC4-17000 ECC Registered RDIMM 288-Pin 2Rx4 1.2V memory RAM module, with the exact same specifications as Hynix part numbers HMA42GR7AFR4NTF, HMA42GR7BJR4NTF and HMA42GR7MFR4NTF. ECC REGISTERED UPGRADE: This type of memory is used in Workstations and Servers. It will NOT be compatible with standard desktop computers. Also, it cannot be mixed with UNBUFFERED memory. 100% COMPLIANT: With JEDEC-Standard specifications, ROHS Compliant, Warranty Safe Upgrade. Designed and Tested to Meet or Exceed all Manufacturer OEM Specs. MAXIMIZE YOUR SERVER: With OWC's ECC Registered Server Memory, you will extend the life of your old infrastructure or save money when building a new one. INDUSTRY LEADING: Consumer-friendly Advanced Replacement Program and Limited Lifetime Warranty, which includes Free Tech Support by Other World Computing.