|Function||Channeling Elemental energy, melee combat, climbing|
|User(s)||Toa Metru Onewa (formerly)|
|Status||Transformed into Stone Hammer|
The Proto Pitons were Toa Metru Onewa's Toa Tools. They allowed him to swing from building to building and climb them with ease. They could also channel his Stone Elemental Powers and control over Stone. These were lost when Onewa transformed into a Toa Hordika, but he later regained them when he was turned back into a Toa Metru. When he became a Turaga, they were transformed into the Stone Hammer.
In the Toa Metru Onewa set, the Proto Pitons' chains were made of slightly softer plastic, allowing them to swing a bit.
- In the movie BIONICLE 2: Legends of Metru Nui, Onewa uses only one large Proto Piton.
- In BIONICLE Heroes, Proto Pitons are the second weapons Hewkii uses. They were later upgraded to the Laser Axe.