Features: Accuracy: The precision milling technology is adopted on the base level of the flat working face, which makes the overall accuracy of the ruler reach 0-0.5mm/m Smooth Surface: Wear - and smooth paint surface, using advanced -stick coating pure polyester ive surface, after powder spray paint, paint or anodic oxidation Horizontal Bubble: High-definition amplification of horizontal bubble, put large fluorescent bubble design, can measure horizontal, vertical and a variety of angles of three lines, more accurate measurement Explosion-proof: Organic explosion-proof, ive cover, effectively the horizontal bubble, greatly extend the life of the horizontal bubble Magnetic: Side strong magnetic suction design, double strong magnetic suction, can be absorbed on the metal surface Specification Material: Aluminum alloy Color: Colorful Length: About 30cm/11.8inch, 40cm/15.7inch Package included: 1pc x Level Ruler