The product is a chemically-biologically processed parietal leaf of the pericardium of a calf. Animals undergo a strict veterinary and sanitary examination, confirmed by a veterinary certificate. To date there is no objective evidence that the type of animal (pig, cattle, horse, sheep) that is the source of raw materials for the manufacture of patches can directly affect the biological compatibility and safety of the product (it can affect the physical and mechanical parameters due to different anatomy). To the maximum extent, this depends on the processing that the raw material goes through. After deep cleaning and processing the material is almost transformed into a biological polymer. There are hundreds of ways and dozens of approaches to pericardial processing. All methods that have proven their effectiveness in clinical practice are based on the decellularization procedure and maximum preservation of native tissue architectonics. Therefore, experienced specialists do not pay attention to the source of raw materials when choosing a patch, but look at the clinical effectiveness of the product in the long term postoperative period.