The two hands, with the upper parts of the arms and palms twisted in a curved shape, when turned obliquely and facing downwards, are known as Āviddhavakraka hands. These should be recognized accordingly.
When the two hands are in the shape of a serpent's head, with the middle finger and thumb touching, and are stretched obliquely, they are known as Sūcīmukha hands.
When the hands are in the shape of a serpent's head, with the middle thumb stretched out, they are known as Sūcīmukha hands, placed in the position of the Svastika.