Officer's dress whites.
naval dress uniform
A naval uniform designed for non-combat, parade and ceremonial use. Just like the military dress uniform of other branches, they usually have more distinctive designs, that show various insignias and other decorations like medals or ribbon bars. As well, naval dress uniforms tend to be clearer in showing rank or rate than those of land or air forces, with officer ranks displayed as bands on the cuffs and/or shoulder boards, and enlisted rates displayed on the upper arms.
Examples
See also
This tag implicates naval_uniform (learn more).