Genuine Original Lenovo 43N3428 ThinkPad Serial ATA Hard Drive Bay Adapter III
P/N: 43N3428. A Lenovo Serial ATA Hard Drive Bay Adapter III for 2.5" SATA Hard Disk Drives (HDDs) as per photos. The Lenovo website states that it is compatible with the T430, T420, T520, W530, W520 series of Thinkpads.