What are the expected values associated with the container_iso' field from the API?

This article details where the standard values returned in the 'container_iso' field can be referenced

The container_iso values that our API returns are provided by the carriers themselves and should be standardized according to the Container Services International definition located here.
For example, a "container_iso" value of "22G1" means the length is 20 feet, the height is 8 feet 6 inches, and the container overall is intended for general purposes.