Abstract: An add-on device (DHD) for disk drives (D) for a multidisk system containing a plurality of drawers (T) includes a metal base support (S) for a disk drive (D), an opening (O) into which an external connector (CN) of the device is inserted, a mechanism for inserting, extracting and locking (PO, R, R1-R2) the device in a selected slot of the drawer, air passages for ventilating the disk drive, a first printed circuit board (CCE) for interconnecting the disk drive with its external environment, and a second board (CCT) connected to the first printed circuit board for supporting DC voltage conversion functions.

Abstract: An apparatus (T) for housing a mass memory subsystem (SSM.sub.1 -SSM.sub.3) that is connected to at least one host system (H.sub.1, H.sub.2) is provided. The apparatus includes a plurality of compartments, each compartment receiving at least one of a plurality of groups of disk units (101-112, 201-212, . . . , 601-612); at least one electrical supply unit for supplying electrical power to the disk units; a plurality of plates (P1-P6) having a central portion about which the compartments are arranged. The compartments carry the disk units. The central portion includes an electronic card to which the disk units are connected. The electronic card provides real-time management of disk units and connection of the disk units to the host system. The apparatus has a front portion (PAV) adapted to house the plurality of plates that are slidably insertable into the front portion and are arranged parallel to each other.