# Hand
## Extended SubModel
A hand is a specific type of part. HandModel inherits from PartModel. Therefore, it contains extra variables that are described bellow:
#### References
* **Bones:** Wrist bone.
* **Parts:** Thumb, index, middle, ring and pinky fingers.
* **Points:** Palm points, ray and midpoints.
#### Palm points
* **Palm center:** Most interior point of the surface of the hand. For both hands:
* **Right** direction (red) goes from palm center to wrist.
* **Up** direction (green) goes from palm center to thumb knuckle.
* **Palm normal:** Point that shares same position as palm center but with different rotation. For both hands:
* **Forward** direction (blue) matches normal vector of palm surface.
* **Palm exterior:** Palm line point under pinky knuckle.
* **Palm interior:** Palm line point under index knuckle.
* **Pinch center:** Midpoint between thumb tip and index tip.
* **Throat center:** Midpoint between thumb knuckle and index knuckle.
* **Ray:** Point where forward vector of each of its representations represents the direction the hand is pointing towards.
## Extended SubView
HandView offers two functions to toggle hand visuals and physics:
* SetHandVisuals (bool enabled, string representationKey)
* SetHandPhysics (bool enabled)
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