In addition to preventing air flow through the engine bay, the stock rain guard also weighs in at 4.5 pounds. After market fan shrouds are good at getting the heat out, but aluminum versions weigh almost 9 pounds including fans, and I assume the stainless steel offerings are even heavier. In addition fans require wiring, fusing and a relay.
These laser cut 6061 aluminum plates provide a mounting point for your stock rubber bumpers while weighing just 1.4oz per pair. Powder coated in gloss black (prototypes shown were not coated). Note: You will be using screws and rubber bumpers from your existing rain guard - you are only buying the plates.
In the words of Colin Chapman, founder of Lotus, "Simplify, and add lightness"