As an industrial and scientific worker, I can confidently say that the NINDEJIN woodworking mandrels are a game-changer when it comes to hole saws and accessories. When I tried this product, I was amazed by the smooth and precise cuts it produced.It made my work so much easier and efficient! The mandrels are made of high-quality materials, ensuring durability and longevity. The only downside is that it may not fit all sizes but overall, I would highly recommend this product to anyone in need of a reliable mandrel..