The optimised shape, and roughening by means of pyramids acting as friction enhancers on the faces of these armour units, increase ACCROPODE™II interlocking, while new features include:
- minimised rocking and settlement,
- maximised energy dissipation,
- reduced wave reflection and run-up/overtopping,
- improved structural strength.

During the design stage, the stability coefficients are selected as a function of the achievable packing density on site.
The standard Hudson’s design KD values for breaking or non-breaking wave conditions are:
•     16 on breakwater trunk sections
•     12.3 on breakwater roundheads

Alternatively, the recommended Van der Meer stability number is:

NS = HS/(∆ Dn50) = 2.8 where HS = significant wave height ∆  = relative mass density Dn50 = nominal diameter