Syntec Quarter Round PCD Cup Wheels are manufactured with premium grade polycrystalline diamonds. While PCD's may be very wear-resistant, they are not impact resistant. It's imperative you watch out for joints, bolts, and anything else made from steel. Great for removing thick coatings, epoxy, and other membranes. Syntec has served the diamond tool industry for decades, leading to the highest quality diamond tools available. Try the Syntec difference today!