Dell - Ddr4 - Module - 64 Gb - Lrdimm 288-Pin - 2666 Mhz / Pc4-21300 - 1.2 V - Load-Reduced - Ecc - Upgrade - For Poweredge C4140, Poweredge Mx740, Mx840, R6415, R7415, R7425, R840, R940, Xr2