Strand is an element of rope consisting of an assembly of wires of appropriate shape and dimensions laid helically in the same direction in one or more layers around a center.

single

SINGLE (N)

Single wire core with six wires (same diameter).
The lay length of each wire layer may be different.
SEALE

SEALE (S)

The number of wires of the outer layer is the same as of the inner layer. The lay length is the same for all wires.
warrington

WARRINGTON (W)

The number of wires of the outer layer is twice the number of wires of the inner layer. The lay length is the same for all wires.
filler

FILLER (F)

Parallel lay strand construction having an outer layer containing twice the number of wires than the inner layer, with filler wires laid in the interstices between the layers.
Warrington-Seale

WARRINGTON-SEALE (WS)

This layer consists of a central Warrington strand and an additional outer wire layer (similar to the Seale design). Construction design is one of the most common strand designs.
compact

COMPACTED STRAND (K)

A strand which has been subjected to a compacting process such as drawing, rolling or swapping whereby the metallic cross-sectional area of the wires remains unaltered whereas the shape of the wires and the dimensions of the strand are modified.