Which rank is indicated by the insignia of three chevrons?

The rank indicated by the insignia of three chevrons is indeed Petty Officer First Class. Each chevron represents an advancement in rank, and in the United States Navy enlisted ranks, Petty Officer First Class specifically has three chevrons and a perched eagle above them.

In the context of the rank order, Petty Officer Third Class has only two chevrons, while Senior Chief Petty Officer and Master Chief Petty Officer feature additional insignia to represent their higher positions. Understanding the insignia and what they represent is crucial for identifying ranks accurately within the Navy's hierarchy. Thus, three chevrons clearly denote the rank of Petty Officer First Class, distinguishing it from the ranks of Petty Officer Third Class, Senior Chief, and Master Chief.