GA standard belongs to Browne &；; Sharp metering system was first used in medicine and jewelry field! The larger the number, the smaller the diameter. Later, it was popularized, and it can also represent thickness. When non-ferrous metal plates and steel plates are both ×× Ga, in fact, the thicknesses are different, and the values of plates and pipes of ×× Ga are also different.

22GA is equivalent to 0.8 in metric system and 0.03 in English system, so it can't explain what material it is.

-I found it online.