Industrial and Scientific category is where these framing squares belong as they deliver accurate and reliable measurements every time, based on our own experience. The thick aluminum construction makes them sturdy and long-lasting, and the white-on-black markings are easy to read. The multiple measurements are also a convenient feature.The only downside we encountered was the difficulty in marking on the surface due to the non-magnetic property. However the precision and durability of these framing squares more than make up for it. Overall, a great purchase for any professional or DIY project..