OWC 64.0GB UPGRADE: Consists of Four 16GB DDR4 2666MHz PC4-21300 CL19 ECC Registered DIMMs 1.2V 288-pin Memory Module with Mac qualified Thermal Sensor EEPROM 100% COMPLIANT: With JEDEC Standard Specifications, ROHS Compliant, Warranty Safe Upgrade. Designed and Tested to Meet or Exceed All MAC Specifications for Mac Pro 2019 7,1 Tower and Rack and 2017 iMac Pro COMPATIBLE PART NUMBERS: , CT32G4RFD4266, CT16G4RFD4266, CT64G4YFQ426S, HMA82GR7CJR8N-VK, HMA82GR7AFR8N-VK, HMA84GR7CJR4N-VK, HMAA8GR7A2R4N-VN, M393A8G40MB2-CTD, M393A4K40BB2-CTD, M393A4K40CB2-CTD COMPATIBLE WITH: 2019 Mac Pro 8-Core (Model ID: MacPro7,1) and 2017 iMac Pro 8-Core (model ID 1,1), 2017 iMac Pro 10-Core, iMac Pro 14-Core, iMac Pro 18-Core INCREASED PERFORMANCE: Memory Upgrades are the Most Effective and Easy Way to Boost the Performance in Your Mac Pro INDUSTRY LEADING: Consumer Friendly Advanced Replacement Program and Limited Lifetime Warranty, which Includes Free Tech Support by Other World Computing OWC 64.0GB UPGRADE: Consists of Four 16GB DDR4 2666MHz PC4-21300 CL19 ECC Registered DIMMs 1.2V 288-pin Memory Module with Mac qualified Thermal Sensor EEPROM Product Specs: Size: 288PIN, SDRAM DIMM, 1024M x 72, Dual Rank ECC Registered Memory Module, Data Rate = 2666MHz, Module Bandwidth 14.9GB/s, CL21, Voltage 1.2V, Specified Thermal Sensor, RoHS Certified, Warranty Safe Upgrade. OWC Memory Compatible With Mac Pro 2019 fully meets specifications with special attention to proper thermal specifications. I