Here's why:

* MCM stands for thousand circular mils. It's a unit used to measure the cross-sectional area of a wire.

* AWG is a standard numbering system used for wire sizes, with larger numbers indicating smaller wire diameters.

* The conversion between MCM and AWG is not linear, but there are tables and calculators available to find the equivalent sizes.

Important Note: It's crucial to consult electrical codes and specifications for specific applications when choosing wire gauges.