This page shows the different variations of the Mini USB B from an Icons8 icon pack. Feel free to resize and recolor the icon, and then download the icon in PNG format for free. Icons are available in PNG and vector.
The main shape is a rectangle that is longer than it is tall with five small rectangles connected to the inside of the top of the rectangle. On top of the rectangle is a shape that is three quarters of a rectangle with two diagonal lines that connect to the top of the main rectangle.