Phra Somdej Wat Ketchaiyo was the first to be made during King Rama IV period and were either given away or hidden in the chedi of Wat Chaio Woraviharn (Ketchaiyo). It is believed that they were made as a merit devoted to his mother and grandfather as his mother’s hometown is near Wat Chaiyo and her maiden name was Ket, Chai was his grandfather’s name and hence the amulet is called Phra Somdej Ketchaiyo.