During the initial stability test of the Basalton Qattroblocks, conducted for the Afsluitdijk Project in 2017, the stability of the block was so high that it could not be tested to its full capacity. At the time, the stability factor was set at a lower limit of 1.37. After the new tests, the stability factor of the Basalton Quattroblock was established to be no less than 1.64. The Basalton Quattroblock remains the most stable revetment unit for revetments and shores.