In communications cables--including fiber-optic cables--having the transmission media wrapped helically around a central member, the longitudinal distance along the cable required for one complete helical wrap; i.e., the total cable length divided by the total number of wraps. Note 1: In many fiber-optic cable designs, the lay length is shorter than in metallic cables of similar diameter, to avoid overstressing the fibers during the pulling associated with the installation operation. Note 2: The wraps, i.e., turns, that are referred to should not be confused with the twists given twisted metallic pairs, i.e., wires, to reduce electromagnetic coupling. Pairs of optical fibers are not given such twists. Synonym pitch.