A jack-up crane vessel is a special ship used to install foundations and offshore wind turbines. Its main features include a heavy crane that can lift between 300 and 3,000 tons, and a jacking system that allows the ship to lift itself above the water to stay stable, even in rough seas. It has a large deck, tall structures to hold the crew and workers, and a helipad for helicopters. It also uses a dynamic positioning (DP) system, which uses GPS to keep the ship in the same spot without needing external help. These ships are usually about 180 meters long and 65 meters wide. Thanks to its jacking system with legs, it can work in water depths of 65 meters or more.