Hello!
This is a hot air balloon made with Blender3.1. Each part is set separately in the stl file. The Fbx file has a simple material color. There is no rope between the balloon and the gondola. If you 3D print, there is a hole for the string to pass through, so please connect it through that hole. Unit in Blender is set to 0.001, millimeter scale. I think that the slice software ChituBox will display it in the same scale. Enjoy!