Conversion from nTopology to CATIA is not supported yet :(

nTopology is a versatile, industry-leading data preparation and STL editor software for Additive Manufacturing that allows you to convert files to STL, repair errors, edit your design and prepare your build platform.

CATIA is a multi-platform software kit for CAD/CAM/CAE, PLM and 3D, created by the French company Dassault Systèmes.

Commonly referred to as a 3D PLM software suite, CATIA supports all stages of product development, including conceptualization, design, engineering and manufacturing. CATIA facilitates collaborative engineering across disciplines around its 3DEXPERIENCE platform, including surfacing & shape design, electrical, fluid and electronic systems design, mechanical engineering and systems engineering. CATIA facilitates the design of electronic, electrical, and distributed systems such as fluid and HVAC systems, all the way to the production of documentation for manufacturing.