Floating sheerleg

A floating sheerleg or simply sheerleg is a floating water vessel with a crane (the "sheerleg" itself), which, unlike a crane vessel, is not capable of rotating its crane independently of its hull.
There is a huge variety in sheerleg capacity. The smaller cranes start around 50 tons in lifting capacity, with the largest being able to lift over 4000 tons. The bigger sheerlegs usually have their own propulsion system and have a large accommodation facility on board, while smaller units are floating pontoons that need to be towed to their workplace by tugboats.