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 stainless steel knurled nuts. pure copper for easy use.It is 200mm sizes.There are even two end vertical scales to draw precision parallel lines to the edge of your work. MINIMUM ACCURACY OF 0, 25MM- 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, allowing you to make a dot with a pencil or to mark a line accurately within the width of a hair!The scale, being recessed and engraved in black, is easy to read. CLEAR ENGRAVING- Engraving scales with laser clear and precise Imported 0.5mm pencil makes the line more smooth, The surface is non-reflective and allows even tired eyes in dim light to mark the exact start. Select the appropriate 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, a long line, a short line, a parallel line and a right angle line, meeting your various marking needs. allow simultaneous marking and measuring on the top, edge and corners! SUITABLE FOR- Suitable for positioning and marking woodworking mortise and tenon work. The right angle ruler is exactly what you need for layout and measuring along the edge of a board or other piece. 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! 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.