QNAP 4GB DDR4 2400 MHz SO-DIMM Memory ModuleKey Features For the QNAP TS x51D and TS x53D 4GB (1 x 4GB) Capacity 2400 MHz Clock Speed PC4 19200 Designed for the QNAP TS x51D and TS x53D NAS Enclosure, the 4GB DDR4 2400 MHz SO DIMM Memory Module from QNAP is a single RAM module that will let you upgrade the overall memory capacity of the NAS. It features a capacity of 4GB, a clock speed of 2400 MHz (PC4 19200), and 260 pin SO DIMM form factor. Applied Models: HS 453DX,TVS 951X, TBS 453DX