The unique curved pentagonal shape fits comfortably in hand, while remaining close to a cylindrical shape commonly used. this shape is used to transmit torque force during any operation requiring an action of tightening or loosening. Complies with ASTM F 1826 / IEC 61235 standards. The terminal tube is a round tube built on a rigid, waterproof polyurethane foam. The circular terminal tube™s shape meets all requirements of the ASTM F711 / CEI60855-1 standards. The locking elements are self-searching when stick is deployed by sturdy bi-material button.