STAINLESS STEEL RULER BODY- The ruler is made of stainless steel with precision manufacturing, clear scale, CNC machining and comfortable texture. The vertical adjustment knob uses pure copper knurled nuts for aeasy to use. There are 200/300/400mm sizes for customers to choose from. There are even two end vertical scales for drawing precision parallel lines to the edge of your work. 0.25MM MINIMUM PRECISION- The minimum precision of 0.25mm makes the operation more precise and reduces the error. The ultra-precise marking ruler has tiny holes and slots at each graduation, you making it possible to make a point with apencil or mark a line accurately within the width of a hair! The scale, being recessed and engraved in black, is easy to read. CLEAR ENGRAVING- Clear and precise laser engraving scales. The imported 0.5mm pencil makes the line smoother, The surface is non-reflective and allows even tired eyes in weak light to mark the exact start. Selectappropriate slot or hole, insert a 0.5mm mechanical pencil and mark the measurement with absolute precision. MULTIPLE FUNCTIONS- Achieve multiple functions including horizontal line, vertical line, long line, short line, parallel line and right angle line, meeting your various needs ofmarking. The 90 shape keeps it perfectly in place while the dual scale surfaces allow you to mark and measure on the top, edge and corners simultaneously! SUITABLE FOR- Suitable for positioning and marking woodworking mortise and tenon work. The right angle ruler is just what you need for laying out and measuring along the edge of a boardor another room. Micro-fine marking holes at each scale line allow you to instantly locate your sharp pencil tip or trace exactly on target without any guesswork or eye strain! Ready to work Adjust the spine fine-tuning knob so that the ruler is aligned with the edge of the spine in a vertical state; While writing, fix the bracket with your left hand, bring the right edge of the bracket close to the measurement object, and put the ruler on the surface of the object; With your right hand, you can use a mechanical pencil to draw lines. Horizontal line Using the upper and lower edges of the ruler and the scale on the surface, you can complete the horizontal marking. Vertical Travel You can pass the tip of the pen through the small round hole corresponding to the scale and move the engraving ruler backwards or forwards with both hands to complete the vertical trace. Short horizontal line Horizontal lines, vertical lines, short parallel lines, etc. They can meet your different marking needs. This line ruler is suitable for positioning and marking in mortise and tenon work. Fineer scale The top of the ruler This row can be accurate to a scale of 0.25mm and is made up of four rows of small round holes: The first round hole is a full scale, conforming to the millimeter scale; The second round hole is full scale + 0.25mm; Third round hole is full scale + 0.5mm; The fourth round hole is full scale + 0.75mm. The bottom of the ruler This row is a longitudinal marking hole with an accuracy of 0.5 mm, consisting of two rows of flat holes: The bottom line is the millimeter scale, which is the millimeter scale; Top line is full scale + 0.5mm.