Knight Bus model kit

The standout feature of the DIY wooden model Knight Bus is its ability to transform by narrowing or expanding its width with a twist of the magical manipulator. Twist the knob on top of the bus counter clockwise and the bus becomes narrow, for squeezing between traffic. Twist the knob clockwise to expand the bus [and any passengers] to their true size. But here’s the amazing thing – as the width of the bus changes, so does the speed! In its normal [not compressed] state, the bus travels astonishingly fast. Compress the bus and an internal mechanism makes the bus travel in slow motion. From the Harry Potter series.