but cuff buttons and substantive rate badges are. This is worn with plain blue mess trousers and (optionally) the peaked cap. Those senior ratings who have not applied for mess dress for 2B dress may instead wear 1C dress with a black bow tie substituted for the black straight tie. No. 3 dress This is the same as the various types of number 3 dress as worn by commissioned officers. Senior ratings wear shoulder rank slides with 3A, 3B and 3C but WO1s may optionally wear shoulder boards with 3A and 3C dress. No. 4 dress Senior ratings currently wear the No. 4 RNPCS dress. White uniforms These are the same as the white uniforms currently worn by commissioned officers. Like with commissioned officers, a white tunic may be worn with 1AW dress and 1BW dress when "required to conform with accepted international standards of dress on state or major ceremonial occasions, but the white tunic worn by senior rates differs from that of commissioned officers in that it only has four buttons rather than five and does not feature shoulder boards nor fittings for them. Petty officers wear blue on white versions of their substantive rate, trade, and good conduct badges with the tunic, Chief Petty Officers wear their cuff buttons and a gold on blue trade badge above the right cuff, and Warrant officers wear gold on white versions of their sleeve rank badges. Medals and rate shoulder badges only are worn with the bush jacket. WO1s may wear optional shoulder boards with the bush jacket as well. When armed, senior ratings wear white gaiters and white webbing belts, as with the blue version. Junior ratings No. 1 dress This is the formal uniform worn on ceremonial occasions. For junior ratings it is a traditional navy blue suit. It is divided into 1A (with medals and bearing arms), 1B (same as 1A, but without arms), and 1C (with medal ribbons). Female personnel may wear skirts except when carrying a sword or rifle. In 1A dress, when armed, a white web belt and white gaiters are worn. The current uniform for junior ratings dates in its present form from 1906, replacing an earlier version introduced in 1856 that featured an untucked frock instead of the navy blue seaman's jumper, that was itself based on the traditional (but unregulated) dress of the seaman. No. 2 dress Mess dress is not