The strand is built up by individual wires which are laid around the core in one or more layers, typically to one of the following constructions:

Ordinary lay wires - all wires are in the same size.

Seale (S):
Parallel lay wires - different size, same number of wires in outer and inner layer.

Warrington (W):
Parallel lay wires - the outer layer of wires has two different sizes, twice as many outer wires as inner wires.

Warrington-Seale (WS):
Parallel lay wires - a combination between Seale and Warrington, with three or more layers of wire.

Filler wire (F):
Parallel lay wires - twice as many outer wires as inner wires, with small wires to fill the spaces between the large wires.

Compacted strand:
A strand that has been formed through compaction maintaining the steel area whilst increasing the fill factor.