A rigid support base has flat parallel top and bottom surfaces. The top and bottom surfaces are separated by a thickness. The support base has a plurality of holes. A plurality of rigid rods is provided. Each rod has a lower end. The lower end is received and retained within an associated hole. Each rod has a notch. Each notch includes an upper ledge. The upper ledge is provided parallel with the top surface of the support base. Each notch includes an angled lower ledge. The lower ledge depends from an associated upper ledge.