The twelve principal channels are arranged in six yin and yang pairs, each pair sharing an element and a limb. Large Intestine is the yang partner of the Lung: both run in the arm, both belong to Metal, and the tradition treats them as an interior and exterior aspect of one thing rather than as two independent systems. That pairing structure is what allows a practitioner working in this tradition to treat one channel with reference to the other, and it is repeated exactly across all six pairs.
The Large Intestine channel carries the point that is, by a wide margin, the most frequently needled in the world: Hegu, Large Intestine 4, in the web between thumb and index finger. Its classical reputation is for the face and head rather than for the intestine, which is a good illustration of a general feature of the system. A channel's points are not confined in their traditional indications to the organ the channel is named for, because the channel is understood as a route rather than as an organ's territory.
Hegu also carries a traditional caution: practitioners in this tradition are taught not to needle it during pregnancy. The atlas records that as part of the teaching rather than as a clinical statement, and takes no position on any physiological question.
The modern point codes, LI4 and the rest, are a twentieth century standardisation adopted to make the classical Chinese names transferable between languages.