This 3D model represents a Hydraulic Cylinder Assembly, a key component used in fluid power systems to generate linear motion and force. The model includes major parts such as the cylinder barrel, piston, piston rod, end caps, and mounting joints. Hydraulic cylinders are widely used in industrial machinery, construction equipment, automotive systems, and heavy engineering applications. The transparent cylinder body in this model helps visualize the internal piston movement and working mechanism. This project demonstrates assembly modeling, mechanical design, and visualization techniques using Autodesk Inventor Professional 2026. It was created as part of a CAD practice series to improve understanding of real-world mechanical systems.