In addition to the rigid shell, the robo shark features several soft, flexible parts, which are likely made of poly vinyl chloride or PVC.

PVC is widely used in a durable, flexible form (Material Properties, n.d.). To verify this, the soft components underwent a cut test, showing a hardness and consistency similar to the PVC sample piece.

Further testing of the suspected PVC components involved heating them with a heat gun. The parts became malleable quickly, a characteristic consistent with PVC (Material Properties, n.d.)