Change into a purple robe. Those with yellow waist and yellow belt are officials with three or more products.

According to the records in the Book of the New Tang Dynasty Che Fuzhi,

The robes of three or more articles are purple, with gold belts and thirteen belts (belts with suspenders on them are also used for decoration).

Four robes deep and eleven gold belts.

Five robes are shallow and ten gold belts.

Six robes are dark green with nine silver edges.

Seven robes are light blue, and the silver belt is nine.

Eight robes are dark blue,

Jiupin robe is light blue and jade has eight rings.

Outgoing officials and Shu Ren are all dressed in yellow, with seven belts of copper and iron (in the first year of the General Chapter, outgoing officials and Shu Ren were forbidden to wear yellow, as mentioned above).

In the second year of Longshuo in Tang Gaozong (AD 662), it was changed to green for fear of dark blue and purple (indigo was dyed many times in ancient times, so it was afraid of being mixed with purple).

From the Spring and Autumn Period (reign from 685 BC to 643 BC) when Qi Huangong wore purple robes, the color pattern of clothes with purple as the top grade was determined, and it remained until the Song and Yuan Dynasties. It was not until the Ming Dynasty that it was changed to big red.

The so-called jade belt usually refers to a leather belt decorated with jade, which is a symbol of the taste of ancient officials. This kind of jade product used to decorate belts is called "belt", commonly known as jade belt board. The early jade belt is a kind of diéxiè, that is, the belt is decorated with jade and many hooks, which are used to hook gadgets or accessories. There is only a cymbal (tā ng, music hall) and a buckle in the belt, and there is no thallium (tā, music it) tail.