This product is either discontinued or we cannot get that from suppliers.
Qnap RAM-2GDR3L-SO-16, 2GB DDR3 Ram, RAM-2GDR3L-SO-1600, DDR3 SDRAM, Speed 1600 MHz, 204-pin, FF SoDIMM, Compatibility QNAP TS-x51 NAS Box.
The 2GB 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.