This is a 3D model presenting diagnostic features of d-TGA at 20 weeks of gestation in axial sections. Plenty of prenatal diagnosticians still have difficulties with diagnosing this anomaly despite many descriptions in the literature. In the opinion of authors, the reason is lack of geometry understanding of this anomaly. The model shows all representative views including four-chamber view (4CV), five-chamber view (5CV), right outflow at the level of classical three-vessel view (3VV) wg Yoo, three-vessel and trachea view (3VTV), and transverse aortic arch view. Our model may be used on-line (with the presence of the patient) at the time of fetal cardiac evaluation in order to understand the mutual geometry of the segments and particular elements constituting abnormal cardiac anatomy of d-TGA. Our model is easy to use for the off-line learning (without the presence of the patient) by relating axial cardiac views demonstrated by means of video clips, still images or schematic drawings from textbooks or publications.