I went by the pro shop and picked up a dozen ProV1x and didn't realize until after I left that I picked up a box marked with a "Play 66" sticker on the outside of the box. The sticker indicated that it came with a free mini-sharpie, which I didn't get (but that's neither here nor there), and all of the balls are numbered 66. I know that you can customize numbers, but this appeared to be a particular promotion for the #66. Anybody know what this is promoting?