Kongosho (Vajra; a ritual implements in Exoteric Buddhism and Tibetan Buddhism) (金剛杵)

Kogosho, vajra in Sanskrit, is a ritual object in Esoteric Buddhism and Tibetan Buddhism.

It became a ritual object by comparing the way Buddha's teachings destroy earthly desires and reveal aspiration for Buddhahood (mind seeking for enlightenment) to a weapon in Indian mythology.

Shape
Basically it has a stick shape with a grip in the center, and spear-shaped edges at the top and the bottom of the grip. There are some variations with different numbers and shapes of the edges, each of which has its own name. There is also one with an ornament of an ogre's face on a grip, which is called Kimen Kongosho (vajra with ogre-face).

Mythology
In Indian mythology, vajra is a weapon of Indra (Taishakuten). As shown in its Chinese name of '金剛杵' (diamond and pestle), it is made of kongo (a very hard metal or a diamond) and wields thunder.

Japan
It is considered to be brought to Japan from China between the Nara period and the Heian period. It has been used in ceremonies of Esoteric Buddhism such as Goma (holy fire) and laid on an altar. Although imported goods were used in older times, domestic ones have increased since the Heian period and today few imports are used in Japanese temples.

Principal gods who wield vajra
Taishakuten (Indra)
Shukongoshin (vajra-wielding gods) (Vajrapani)
Kongo Rikishi (Vajradhara, Nio [guardians of a temple])
Basara Daisho (Vajra, one of the Juni Shinsho [the 12 protective gods])

Major vajra

Tokkosho (also known as Dokkosho)
A vajra with a spear-shaped edge each at the top and the bottom of a grip.

Sankosho
A vajra with three separate edges like a fork.

Gokosho
A vajra with four edges surrounding an edge in the center.

Nanakosho
A vajra with six edges surrounding an edge in the center.

Kyukosho
A vajra with eight edges surrounding an edge in the center.

Hojusho
A vajra with nyoi hoju (a sacred gem, said to remove suffering, and be capable of granting every wish), instead of edges, at the top and the bottom of a grip.

Hotosho
A vajra with hoto (a treasure pagoda), instead of edges, at the top and the bottom of a grip.