A memory stick includes a -shaped metal plate member having two tenones respectively protruded from an inner wall thereof at two opposite sides and aimed at each other, each tenon being formed on the -shaped metal plate member by means of punching the inner wall of the -shaped metal plate member with a punch to form a protrusion and then punching the protrusion with a punch rod to extend the height of the protrusion and to deform the protrusion into a tubular configuration, and a casing accommodating a PC board that has a USB connector at its one end and having two pivot holders symmetrically located on two opposite sides thereof and respectively pivotally coupled to the tenones of the -shaped metal plate member for enabling the -shaped metal plate member to be turned relative to the casing to close or open the USB connector.