A block for an underwater mattress

摘要

A block (10) for an underwater mattress M has an outer housing (12) made of a plastics material. Contained within the housing (12) is a body (14). The body (14) comprises a settable material. Extending through the block (10) is a plurality of cables (16) that facilitate the flexible coupling of adjacent blocks to form the mattress M. The block has a maximum foot print of X by Y mm where X > Y. In one specific embodiment Y = 00mm and X = U.Y where U is an integer≥2. Thus for the situation where U = 2 then X = 1000mm. Opposite surfaces of the housing (12) have different coefficient of friction.