Thermoplastic, black grey.
Bush and screw steel 5.8.

Bush black oxidised.
Screw trivalent blue passivated.

The set screw sets the required torque. The knob de-clutches and turns freely when the desired torque is reached.

Δ Add the desired cap colour here. No colour code is required for black grey caps.

1) adjusting screw for setting the torque