The size of the ruler is suitable for 2×4 wood for easy scribing.The ruler can be used to check 45° and 90° at the same time for scribing.The ruler is easy to use and allows you to check the angle of 45° and 90° at the same time.A screw hole guide is included to help you find the right place to put the screws.A 150mm scale is provided.The clear polycarbonate resin makes it easy to see the wood and prevents damage.