an upper case;

a lower case;

a printed-circuit board assembly (PCBA) that comprises:

a circuit board having wiring traces;

a flash-memory chip mounted to a first surface of the circuit board;

a controller chip mounted to the first surface of the circuit board, the controller chip having a input/output interface circuit for interfacing to an external computer, and a processing unit for accessing the flash-memory chip in response to commands from the external computer received by the input/output interface circuit;

a switch, mounted to the circuit board, having a sliding tab protruding through the upper case, the sliding tab being slidable by a user to indicate to the controller chip to prevent writing to the flash-memory chip;

contact pads formed on a second surface of the circuit board, the contact pads for connecting the controller chip to the external computer;

wherein the second surface is opposite the first surface;

wherein the upper case is attached to the lower case during assembly with the PCBA between the upper case and the lower case, with the contact pads exposed through contact-pad openings between the upper case and the lower case, the upper and lower cases encapsulating the circuit board; and

supporting dividers formed on the lower case between pairs of the contact-pad openings, the supporting dividers supporting the circuit board at a slanting angle to a primary surface the upper case, wherein the first surface of the circuit board and the primary surface of the upper case are non-parallel at the slanting angle,

wherein the flash-memory chip is block-addressable and not randomly-addressable.