A flexible pipe body and a method of manufacturing flexible pipe body and a tape used during the manufacturing are disclosed. The flexible pipe body includes at least one layer of helically wound tape, adjacent windings in the layer of tape being interlocked by a hooked region of a winding nested in a valley region of an adjacent winding wherein the tape has a cross-sectional profile comprising a first contact surface and parallel spaced apart side walls substantially perpendicular to the contact surface.