A 3D view of the model described in the text. The colours represent the magnitude of the velocity field, increasing from the inside (light grey) of the bow-shock component to the outside (dark grey). The direction of the velocity field is indicated with arrows and the motion of the Herbig-Haro object is indicated with a dashed line. The hot component, producing the bump spectral feature is located at the centre of the model and the inclination with respect to the line of sight is 25°. A cut has been made through the top of the model for clarity.