This kite winder is made of a single piece of plastic: an oval grip you hold with your whole hand, with a flared end on each side between which the line is wound. In the photo it carries a thick layer of white line.
At the beach or in an open field you unwind the line as needed, then wind it back between the ends afterwards. There is no handle or brake: this is the simple, sturdy winder that comes with many single-line kites.
The winder is supplied in a variable colour. The photo shows a blue example and, inset smaller, the same model in red; which colour you receive is not fixed.
You receive the winder with the line already on it, without a kite. A spare to keep in the bag for when a line tangles or breaks.