Check out some options how slt files might be converted to jpg format.
It should be possible to create a JPEG image preview of any 3D STL model with any CAD/3D printing program that contains some sort of previewing function. This is useful for sending the model as picture, but it will no longer be useable as a CAD file or used for 3D printing.
Unfortunately, there is no detailed software record in the database for this conversion.
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