Using a 0.5 square millimeter wire harness, with four pairs of four soldered together

Using 2.5 square and 0.3 square millimeter wire bundles for one-to-two soldering.

Using 2.5 square and 0.3 square millimeter wire bundles for pair-to-pair soldering.

What is shown is a 2.5 square millimeter and 0.3 square millimeter wire harness, connected in pairs.