First class and Unmitigated

First class noun - Mail that includes letters and postcards and packages sealed against inspection.

Unmitigated and first class are semantically related. in excellent topic. In some cases you can use "Unmitigated" instead an adjective phrase "First class".

Unmitigated adjective - Having no exceptions or restrictions.

First class and unmitigated are semantically related. Sometimes you can replace phrase "First class" with "Unmitigated", this terms are similar.