Ethylene andor propylene, and \u03b1-olefins may be copolymerized by contacting then with certain iron or cobalt complexes of selected 2,6-pyridinecarboxaldehydebis and 2,6-diacylpyridinebis. The user can switch between multiple independently stored optimized logic applications instantly. A mounting plate is attached to the outer edge and has an upper edge and a lower edge.