This product is either discontinued or we cannot get that from suppliers.
Qnap RAM-64GDR4ECS0-LR-2666, 64GB DDR4 SDRAM Memory Module, DDR4 SDRAM, 2666 MHz, DDR4-2666/PC4-21333, NAS Server, 288-pin, FF LRDIMM.
Designed for their TS-2888X NAS, the 64GB DDR4 2666 MHz LR-DIMM ECC Memory Module from QNAP is a single RAM module that will let you upgrade the overall memory capacity of your compatible NAS.