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 point with a pencil or mark a line precisely within the width of a hair! The scale, being recessed and engraved in black, is easy to read. STAINLESS STEEL RULER BODY: The ruler is made of stainless steel with precision manufacturing, clear scale, machining CNC and comfortable texture. The vertical adjustment knob uses pure copper knurled nuts for easy operation. 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. MULTIPLE FUNCTIONS :Achieve multiple functions, including horizontal line, vertical line, long line, short line, parallel line and right angle line, meeting your various marking needs.90 shape ° holds it perfectly in place while the dual-scale surfaces allow you to mark and measure on top, edge and corners simultaneously! 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 under 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. SUITABLE FOR:Suitable for positioning and marking mortise and tenon work for woodworking. The right angle ruler is precisely what you need for layout and measuring along the edge of a board or other workpiece. Micro-fine marking holes at each scale line allow you to instantly locate your sharp pencil tip or trace exactly on the target without any guesswork and eye strain! Our Service: We are committed to providing you with satisfactory service. If you have any questions, you can contact us at any time. We will reply to you within 24 hours and try our best to resolve the problem for you.