Abstract: The transportation device for a musical instrument, preferably for a cello, is made to fit over a conventional everyday case which is made of a hard material and which is provided with hinges. There is provided a protective cover for the everyday case which is adapted to the shape of the everyday case, is impact resistant and is completely surrounding the everyday case, when the everyday case is placed therein. The protective cover is inflatable and deflatable, and it is surrounded by an outside cover made of a puncture-proof and flexible fabric. The protective cover and the outside cover are attached to each other. Both covers are light-weight compared to the everyday case.