All physical quantities are measured in SI units. When importing geometries, the units which are encoded in the file, are ignored. For example, a length which is encoded as 1000 mm will be imported as 1000 and displayed as 1000 m in SI units. If the geometry is exported in meters, the same length will be written as 1 m and read as 1. Therefore, the model should be scaled such that the numbers which are written in the geometry file have the desired order of magnitude. After importing a geometry, please check the event log to verify that the size matches your expectations. We generally recommend that you use meters when exporting geometries.