The multi-purpose tower was introduced to the market in the late 90s. It is a box girder-type mast which houses all the machinery inside. The multi-purpose tower has the same functionality as a normal derrick but offers additional improved accessibility to the well-centres. This accessibility and its improved handling procedures allow a smaller and much better-integrated vessel. The HuisDrill 12000 and the JBF14000 are good examples of this integration.