I'm confused, new props, look used or something?
 

I have a number of stainless props, new. Brand new, just took them out of the mercury marine boxes.

But on the blades there is like, some scuffing or something. It is obvious this was done on purpose, I just have never seen it and don't know why they look like this.

Anyone???

Example:

I've been seeing that lately. They take a sander and rough up the trailing edges of the blade only.
My guess is to create aeration to get the water off of the back of the blades sooner.
That is a guess only though.

Anyone know for sure?