A portable storage device, such as a USB portable disk drive, comprises a main
body and a rotation arm. The main body comprises a storage portion, a connection
portion and a back portion. The connection portion comprises a first fastening
portion, and the back portion comprises a second fastening portion. The rotation
arm is rotatably connected to the main body, and the rotation arm has a third fastening
portion corresponding to the first fastening portion and the second fastening portion.
When the rotation arm is situated at a first position, the first fastening portion
is engaged with the third fastening portion, and the portable storage device is
at a status of being housed. When the rotation arm is situated at the second position,
the second fastening portion is engaged with the third fastening portion, and the
portable storage device is at a status of being used.
