Petty officer third class
From Halopedia, the Halo wiki
Template:Rank Infobox Petty Officer Third Class is the fourth enlisted rank (E-4) of the UNSC Navy and is the lowest rank of non-commissioned officer, or NCO. Directly above it is Petty Officer Second Class and directly below is Crewman. It is equal to the rank of Corporal in the UNSC Marine Corps, Corporal and Specialist in the UNSC Army, and Senior Airman in the UNSC Air Force.
In informal settings, a Petty Officer Third Class is typically called a "Petty Officer".
In the UNSC Navy, enlisted personnel are referred to by their rating and rate (rank).
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