Refers to a full matching set of items, especially traditional clothing, armor, or gear. Often used in historical or formal contexts.
This armor is preserved as a complete set.
It's difficult to assemble a full set of tea ceremony utensils.
Compound of 皆 (kai, 'all') and 具 (gu, 'tools' or 'equipment'), literally meaning 'all the equipment'. The exact historical derivation is uncertain, but the spelling is conventionally associated with a complete set of matching items.