Abstract: A light eliminator which permits passage of ventilating air but totally eliminates entry of light into the poultry house which includes a plurality of laterally spaced vertical fins or panels each of which is of a unique configuration which breaks the light four times in order to totally block the entry of light into a poultry house while maintaining a minimum air flow resistance with the fins being spaced apart by standoffs that are uniquely positioned with the fins generally being of W-shaped configuration whereby negative pressure within the poultry house provided by air circulating fans will not cause vibration or waffling of the fins when subjected to air velocities induced by high CFM capacity poultry house fans. The light eliminator is constructed of noncorrosive plastic material and can be assembled easily in a short period of time and is extremely durable resulting in low cost operation.

Abstract: A plastic tray for packaging food products is disclosed. The tray has a preferred composition of about 85 percent polypropylene, 15 percent impact modifier or copolymer, 1 percent nucleating agent, and 1 percent density reduction agents.A method of manufacturing a plastic tray of packaging food products is disclosed. The method includes the steps of mixing the polypropylene, impact modifier, nucleating agent and density reduction agents together, heating the mixture at 450.degree. F. to 550.degree. F. under a pressure of about 300 p.s.i., injecting the heated mixture into a mold, and cooling the mixture.