Cutting disc is widely used in our daily life now. But sometimes, although you know the outer diameter and thickness, you still don't know what you need. Cause there T41 and T42 on it. This is the type of the cutting disc. T41 is flat, like the left picture below, T42 is depressed center, like the right picture below.

Regularly, the thickness of Super Thin Cutting Disc is between 1-3mm, it's suitable for cutting metal, carbon steel, alloy steel, stainless steel and so on. The thickness of Depressed Center cutting disc is between 2-5mm, it's suitable for cutting and grinding metal, carbon steel, alloy steeland so on. T42 cutting disc can grind and cut, while T41 cutting disc can only cut. But T41 cutting disc focuses on cutting materials, it's more sharp and higher efficiency than T42 cutting disc.