Conversion from SLDPRT to Siemens NX is not supported yet :(

A SLDPRT file contains a 3D part created in the SOLIDWORKS design software.

Multiple SLDPRT parts can be independently modified and combined into a single SLDASM assembly file. If one SLDPRT part belongs to several assemblies, then after modifying it, the changes will appear in all assemblies.

SLDPRT are proprietary files with closed specifications. Nevertheless, some APIs (like CAD Exchanger SDK) provide the facility to read and convert them to other formats.

In addition to SOLIDWORKS software, SLDPRT files are supported by Autodesk Fusion 360.

A PRT file is a model part file saved in a three-dimensional model format used by Unigraphics, a 3D CAD program. It contains surface and solid information for a single part. PRT files are saved in a binary format, similar to an Alias wire model and an SDRC (Structural Dynamics Research Corporation) model.