This product is either discontinued or we cannot get that from suppliers.
Qnap RAM-8GDR3L-SO-1600, 8GB, Ram 1600mhz, 204pin, Sodimm Memory Module, Compatibility QNAP TS-x51 NAS Box, FF SoDIMM.
The 8GB 204-Pin 1600 MHz SO-DIMM DDR3L RAM Module from QNAP is designed to run at 1600 MHz frequency. The 204-pin module is compatible with the TS-x51, 451U, x53, x53U, and TVS-x63 series.