Generally held that pauldron colour denotes rank/specialisation:
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Designations:
SANDTROOPERS pauldrons designated the following:
* Black – Private
* White – Sergeant
* Orange – Squad Leader
FIELD TROOPER pauldrons designated the following:
* Yellow – Rail Detonator Equipped Field Trooper
* Red – Imperial Repeater Rifle equipped Field Trooper
IMPERIAL MARINES and IMPERIAL SHOCK TROOPER pauldrons designated the following:
* Orange – The normal colorworn by these units. Orange colored pauldron was also standard equipped on the Stormtrooper backpack.
Some regular Stormtrooperunits from around 1.5 years ABY had pauldrons that designated the
following:
* Grey – Bombardier
* Yellow – Rifleman
* Red – Medic
* Blue – Sniper
* Orange – Captain
Phase I Clone Trooper pauldrons designated the following:
* Green – Sergeant
* Blue – Lieutenant
* Red – Captain
* Yellow – Commander
Taken from discussion here:
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