IBM ACLB-RFB is a 300GB hard disk drive for adding storage in a system that supports this drive specification. Its 2.5-inch form factor gives a compact footprint, while the SAS interface is intended for storage environments built around that connection standard.
The drive is specified for 6Gb SAS and spins at 15,000 rpm. These details describe its interface and mechanical operating speed, useful when identifying it for a compatible storage setup. The capacity is 300GB for storing system data, applications or working files. The listing identifies this particular item by the ACLB-RFB product code.