1ALUMINUM ALLOY MATERIAL: Made of premium aluminum alloy material, the ruler is strong and sturdy, ensures long life span. 2MULTI USE: The triangle ruler is used for angle measurement, and the positioning rod is used for cutting. The protractor can be used with the square saw for cross cutting or bevel cutting. The combined square can measure or mark the angle from 0 to 90 degrees very quickly and serve as the saw guide for 45 and 90 cutting. 3ACCURATE CLEAR SCALE: The scale is calibrated by professionals. The scale line is laser printed, coated with low glare and protective powder coating, which is clear and visible, easy to read, and will not wear after long term use. 4WIDE APPLICATION: The ruler is used to measure angles, check water marks, saw guides, adjust saws, draw circles, and mark plates for tearing, leveling, and finding roof slope. 5EASY CARRYING: The ruler is light in weight, thin and small in size, you can easily store and carry it for convenient use.