726719-B21-PCW is a HP Compatible 16GB PC4-17000 DDR4-2133MHz 2Rx4 1.2v ECC RDIMM (generic for HP PN# 726719-B21). This is a 'major brand' module kit (from either Samsung, Micron, Hynix, Infineon, etc.), equivalent in every way to HP original memory. All PCW modules meet or exceed OEM specifications and JEDEC standards.