That is interesting. My white props have the "2" mark as well. These shipped in paired, sealed bags with red props without "2"'s. Does anyone have red props marked with "2"?
I just collected my new props from my PO Box. I ordered 4 sets about a month ago. Each box has a sealed bag with a CCW and a CW prop and each prop has the foam insert; the serial numbers on the boxes are sequentially numbered. Two pairs have the "2" on both props (red and white), one package has the white prop with a "2" and the other is unmarked, and two bags are not marked. I was lucky in that my original props all seem to work just fine, no numbering and no foam.