The vajra is a weapon that is used as a ritual object in which religion?

A vajra is a ritual weapon symbolizing the properties of a diamond (indestructibility) and a thunderbolt (irresistible force).

The vajra is a type of club with a ribbed spherical head. The ribs may meet in a ball-shaped top, or they may be separate and end in sharp points with which to stab. The vajra is the weapon of the Indian Vedic rain and thunder-deity Indra, and is used symbolically by the dharma traditions of Buddhism, Jainism and Hinduism, often to represent firmness of spirit and spiritual power.

In Buddhism, the vajra is the symbol of Vajrayana, one of the three major schools of Buddhism. In the tantric traditions of Buddhism, the vajra is a symbol for the nature of reality, or 'sunyata', indicating endless creativity, potency, and skillful activity. The vajra and bell are used in many rites by a lama or any Vajrayana practitioner of sadhana. The vajra is a male polysemic symbol that represents many things for the tantrika. The vajra is representative of upaya (skilful means) whereas its companion tool, the bell which is a female symbol, denotes prajna (wisdom).