Review on Tungsten Extended Engraving Polishing Drilling by Ryan Cornelius

The variety of types and sizes in this set is great, they work well for many different grinding and sanding jobs. So far they have also held up very well and stayed sharp. I recently used them to port my car's exhaust manifolds which are very hard cast metal. I was very satisfied with their good work. I expected them to be useless after this job, but they remain sharp. Compared to other brands that are much more expensive, the quality is very good for the price!