Welcome my fellow MacProUpgrade members send your offers via the \"make offer\" button and please leave your MacProUpgrade username in the message details field! These kits have matching RAM modules that were removed from working IBM/Lenovo servers during a RAM upgrade when the severs had their 8GB modules upgraded to 16GB modules. The modules will come individually packaged as shown in the photos. Let me know if you have any questions!These kits are 1600Mhz speed but run perfectly at 1333Mhz in the Mac Pro 4,1 / 5,1 - as stated below I\'ll test each kit in my own Mac Pro 5,1 before shipment.IBM Micron 64GB Mac Pro 4,1 / 5,1 Upgrade Kit 8x8GB DDR3 PC3-12800R SDRAM Memory Modules. Each kit is tested to be working in my own personal Mac Pro 5,1 workstation before shipment. Each Kit is also put through at least the first 4 test patterns of MemTest86 to have no errors.