a broad faced , low angle , funnel shaped net leads to a flexible discharge tube of approximately one - quarter larger diameter than the balls play . an upper perimetric frame holds open the net while a base frame is joined to the outlet end of the discharge tube to tension the net and the discharge tube . connecting arms establish a predetermined spacing between the upper and base frames and support the upper frame in its open position . hinged portions of the upper frame allow it to be folded into a compact , &# 34 ; x &# 34 ; shaped storage configuration .