This model is originally created by the uploader and the original software is catia. It contain sketch for people who want to modify for personalised shape, this parametric design is easy to modify with both mesh edit software and CAD softwars. The parametric file is Catia and be sure to open it with version 2019 or higher. And for other files, there are very high resolution file that well meshed with quads. If you have Maya 2022 or higher version, You can directly open the CATPart file and then directly edit the nurbs surfaces.