What is shown is a 2.5 square mm and 0.75 square mm wire harness, one to four.

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

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

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The video shows one-to-one soldering of a 2.5 square millimeter wire harness.

A 2.5 square millimeter and a 0.5 square millimeter wire harness is used, soldered in pairs of three