The invention is directed to a process for the making of a product out of laminated composite material. A flow indicator that is positioned within the conduit so as to be viewed via the viewing port and is positioned so as to not to substantially interfere with a flow of the substance along the path. The lamp housing assembly includes an air distribution assembly having an air chamber that is disposed adjacent to the lamps and pressurized to provide uniform distribution of air exiting the air chamber to impinge a backside of each of the lamps.