This model is a helpful tool to inform patients about kidney stones (nephrolithiasis) and urinary stones (urolithiasis) * It shows an opened right kidney in natural size * The renal calices, the renal pelvis and the ureter are opened as well so that concretions or stones can be identified in the following typical positions: * In the area of the renal pyramids * In the area of origin of the upper calix group * In the renal cortex * In the connecting tubule of the lower calix group, causing congestion of the minor calices (partially closed, partially opened) * In the ureter 4 original color pictures on the base show various kidney stones * Model * Grade 9-Adult