The dorje or vajra was mainly employed in Tantric Buddhism in Tibet, in the Vedic ritual for dispelling evil forces from sacrificial enclosures. As such, it symbolises spiritual forces and firmness of spirit. Bells are often found in opposition or as a complement to the vajra.
Cf. a Ming dynasty Yongle-marked, vajra, together with a bell, in the Beijing Palace Museum, illustrated in Cultural Relics of Tibetan Buddhism, Hong Kong, 1992, pl. 131-1; and a six-point vajra from the 18th century, in the National Palace Museum, Taiwan, is illustrated in Monarchy and its Buddhist Way, 1999, pl. 10.