The special bolt, marked with code number K 28035, is engineered for mounting the main rocker arm K 28005 within the complex mechanism of the ZV40/48 diesel engine. This bolt must withstand extreme loads and maintain the precise geometry of the engine’s moving parts. Its design allows for precise fitting and maximum resistance to bending and shear forces, which is crucial for the smooth operation of the valve system. The reliability of this bolt directly affects engine performance, making proper installation and periodic inspection critically important.