A spiral double-twisted structure is provided having an n-th upper steel wire (An) and an n-th lower steel wire (Bn) which are paired with each other and rotated in one direction to form a front spiral twisted structure having a plurality of twists. Further, a k-th transverse steel wire (Ck) may be transversely...http://www.google.es/patents/US7325774?utm_source=gb-gplus-sharePatente US7325774 - Gabion unit and gabion mesh comprising it
