Lens hood for Canon EF24-70mm F4 L IS USM. It has a bayonet mount to fix on the lens tight.
Actually, commercially lens hoods are not so expensive. But I just want to tried making for exercise. It was a good exercise to learn how to design round shaped object with such the bayonet mount for the lens by FreeCAD macro.
All parameters are defined in the macro, now we can make other types of lens hood by ourselves.