CCM BV, Enersea, Femto and Theuws developed the detailed design which led to a first prototype. At the Theuws yard in Wieringerwerf a functional inspection and water test was carried out with positive results mid-June 2020. At the end of June further tests took place at Sif’s terminal at Maasvlakte 2 in Rotterdam. This time the cover was mounted on a mock up monopile so the complete construction could be tested on functionality, load resistance, water tightness and several other aspects. Also here the test outcome was very promising. Following the successful design and construction of this prototype, Vattenfall decided to grant the production order for the complete 140 monopile covers to the parties involved.