, How:1. Accurate T-ruler measurement: multiple indicators provide the highest marking accuracy, allowing users to accurately mark the best millimeters. The design of the scale and main scale can smoothly slide to the main body, which fits the body perfectly. Compared to conventional calipers, the multi-gauge has a more accurate minimum measuring range. Calipers can mark up to 1/20 (0.05) mm, which is about 0.019 inches.2. Multi-function (Measuring & Marking): You can do 5 different things with this ruler. From measuring 45 degrees, 90 degrees, depth, width to drawing lines. You can measure the thickness and depth of an object like any other caliper, but you can also use a diagonal and square combination to check the angle. You can use the major scale as a ruler to mark objects.3. Easy to read: Each aluminum plate is precision milled using the most advanced MCT equipment, then subjected to grinding and anodizing treatments. Easy to read, heat-resistant, stable to use, and lightweight.4. Stable and lightweight: The blade is made of anodized aluminum with a thickness of 2mm. This stable aluminum tool plate is strong and lightweight. It is 1.06 ounces lighter than regular tweezers. The lightweight body is ergonomically designed to reduce pressure on the elbow or wrist during measurement and marking.5. Removable: you can insert a ruler that will act as a caliper. The measuring instrument is equipped with an additional depth measuring instrument, which is great for measuring cylindrical rods, pipes and various angles. This depth gauge is also detachable. Specification:Material: Aluminum Alloy Model: Size 0-280mm is about 305*100mmSize 0-210mm is about 100*230mmPacking List:1*Woodworking RulerNotes:If you have any questions,