The Tahai complex consists of three platforms: Ahu Vai Uri, Ahu Tahai and Ahu Ko Te Riku. Ahu Ko Te Riku bears a single moai (statue) that presents pukao (topknot) and has eyes of coral and volcanic rock. In the past, these eyes were not attached permanently, but were installed by priests only during special rituals. Red pukao usually weighting several tons were installed without the intention of being taken down and were probably a symbol of nobility, a crown made out of feathers. The statue from ahu Ko Te Riku is thought to be the earliest moai erected on the platform on the Easter Island in about the twelfth century.