Not only do they have a purpose. But they also look really nice.
 
We modeled these Stainless Steel Diffusers after parts that we make for road cars, however the effect of these panels are a little different. These  panels are mounted on top of the winglets at the bottom rear of the front fenders. The Diffusers create a slip stream that pushes water droplets that collect on the mudflap from the road further back and away from the rider to reduce the chance of the rider getting wet.
 
All hardware is included with this kit. Holes will need to be drilled for mounting locations. 3/16 Drill bit is included with hardware.
 
Material is 304 Stainless Steel