HDD Interposers

What are these and what do they do?

The interposer provides the communication for SATA drives when connecting to a backplane that can run either SAS or SATA drives. Its only the SATA drives have the interposer board within the carrier.  The interposer works as the interface to allow communication to the drive when the carrier is connected  to the backplane.

Typical applications:

An example is that these interposers are required if you want to use SATA drives in an HP P2000 G2 /G3 storage systems.