An apparatus includes a casing, an electrical connector, and a latch unit. The electrical connector is provided in the casing, and is coupled electrically to a terminal of a disk drive when the latter is received in the casing. The latch unit includes a latch member that is provided on the disk drive, a first interlocking member that is formed on the latch member, an operating member that is pivoted to the casing, and a second interlocking member that is formed on the operating member, and that engages the first interlocking member when the electrical connector is connected to the terminal of the disk drive. The operating member is operable so as to disengage the second interlocking member from the first interlocking member, thereby permitting removal of the disk drive form the casing.