Final answer:
Enlisted military personnel are required to wear insignias on their uniforms to denote rank, except for non-rated personnel who may wear uniforms without these insignias. Specific regulations vary by military branch and country.
Step-by-step explanation:
The question posed relates to the uniform regulations of military personnel. Enlisted personnel are required to wear insignias on all uniforms to denote their rank, with the exception of non-rated personnel. Non-rated personnel, typically newer members of the military service who have not yet earned a rating or rank, may wear uniforms without these insignias. The specific type of insignia or device may vary depending on the branch of the military and the country's regulations.