I purchased this a long time ago, and do not actually know the grit rating for the product:

Amazon.com: Professional-Grade Dual-Grit Aluminum Oxide Sharpening - Honing Stone: Home Improvement

I was wondering if anyone happened to know the rating on them, or a way to find out. It is obviously much too coarse for any straight razor but works quite well with 3-in-1 oil for knives.