Armour provides protection against waves, surf and undertow. It consists of a filter layer (geotextile or gravel filter) and a riprap frame. The riprap frame can be non-braced, braced or grouted. Armour can be tailored to requirements in terms of thickness and permeability. Colcrete - von Essen has long and wide-ranging experience of all armour constructions. This experience lends weight to the case for braced armour – especially for shipping lanes – because, with maintenance requirements virtually zero, braced armour almost always has the economic edge over non-braced construction. There are also good ecological reasons for using braced armour, which makes for stable and thus enduring habitats for fauna and flora.