An apparatus is provided for making reinforced ply is described. The apparatus includes a cross-head die assembly for use with an extruder, the cross-head die assembly having: an inlet section having an inlet for receiving flow from the extruder; an upper support block removably connected to a first side of the interior section; and a lower block removably connected to a second side of the interior section. A first flow passage is located between the upper support block and the interior section and is in fluid communication with the inlet. A second flow passage is located between the interior section and the lower support block and is in fluid communication with the inlet. The cross-head die assembly further includes a removably mounted die located at an outlet end of the assembly. The first and second flow passage is in fluid communication with an inlet of the die; each flow passage has a raised center rib and an area that decreases from the inlet to the outlet.