Based on his trench coat which has no epaulette on 1950s.
We referred from trench coat as a military garment on WW1 / WW2.
Feature: Combination of high waist position belt which does not disturb footwork and One panel raglan sleeves which widen range of motion by well devised arm hall cutting pattern.
For ALⅢ, its sleeve tabs, waist pocket, tin warmer which placed back-side of top collar are arranged to simplify.