The viewer reads, triangulates and displays 3D geometry from OBJ WaveFront files. OBJ is a text format for describing 3D models, it is supported as export from most widely-used 3D CAD studios like ScketchUp, 3DS Studio Max, DAZ Studio, SOFTIMAGE and many others. The program uses its own triangulation engine for reducing the faces to triangles. For closed surfaces it also calculate normals, if they are not ordered correctly, calculates volumes and surfaces. It also supports materials and textures readed from MTL files. The demo viewer is suitable for small and medium sized objects, comprised from up to one hundred thousand triangles. On the right, the viewer shows a tree with the object hierarchy and the separate meshes, they can be viewed with checking/unchecking the checkboxes next to them. Some geometry paramaters of the meshes are given in the data nodes of the tree. For drawings is used OpenGL.