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 to easy use. It is 400mm sizes .There are even two end vertical scales to draw precision parallel lines to the edge of your work. MINIMUM PRECISION OF 0.25MM - The precision minimum 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 point with a pencil or mark a line precisely inside a hair's breadth! The scale, being recessed and etched 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. 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, a vertical line, a long line, a short line, a parallel line and a right angle line, meeting your various marking needs. 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 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!