The Vajra is used in the practice of Tibetan Buddhism. Viswa Vajra is the thunderbolt or diamond that destroys all kind of ignorance and itself is indestructible. When two thunderbolts are crossed it is called a Viswa Vajra. It is the emblem of Amonghsiddi. In Buddhist Tantra the word generally designates Sunya or Void which cannot be cut, cannot be destroyed, but itself destroys all evils.