The twelve-cornered redented stupa is an architectural form evolved from the basic square pagoda by adding three notches to each of the four primary corners, totaling twelve. This technique creates more intricate lines and a more slender, graceful silhouette compared to traditional solid square structures. In the case of Phra That Duang Diao (Li District), the stupa incorporates later-period artistic influences from the Khru Ba Srivichai school. The pristine white structure features a multi-tiered base, with the bell-shaped body (anda) minimized and transformed into a slender redented pillar reaching skyward, symbolizing refined craftsmanship and the spiritual ascent toward emptiness.