This is a USB light. The light part, which contains a bright low-power LED, measures 37mm x 9.5mm in diameter, and is on a flexible chrome stem 375mm long, ending in a USB A plug.

Having your own mini-light is useful if you're: on a plane, at a lecture, working in bed, or at home and your family have teevee on. It's surprising how much easier it is to type when you can see what you're doing.

The chrome casing contains a bright low-power light-emitting diode and, at the end, a plastic lens. It takes power from the computer's USB socket, so doesn't need a battery or a mains adapter. It uses so little power that it doesn't even get warm when it's permanently connected.

Remember that the light is mechanically supported by the computer's USB socket, so always hold the base when you adjust the flexible stem.