Features: 1 This ruler is made of high quality brass, which has the advantages of high hardness. It will not cause allergic substances and is safe. 2 This ruler is mini small design, lightweight, not easy to deform, which is easy to carry. 3 The ruler is formed by integral stamping, and the surface is finely drawn which is feel smooth and comfortable. 5 Pure brass ruler, brass material, firm, simple, practical and easy to carry. 6 It can be used as outdoor gadgets, painting cartography ruler, bookmark, or school teaching tools, etc. It has a wide range of uses. 7 Unique color charm and color variability, with the use of a long time, copper will occur natural reaction, forming a unique retro flavor, full of sense of age. Specifications: Material:Brass Color:Gold Weight:31.5g/22g Length:13cm/17cm Width:3cm Thickness:1mm Maximum scale:12cm/15cm Ruler Tyoe:Straight ruler Note: About the maintenance of brass: Brass will oxidize the characteristics of long-term use, will be fully oxidized with air and sweat, the color will become dark, especially in summer, the temperature is particularly high, will accelerate the oxidation of brass, especially the part of the hand, because sweat has been in contact, high temperature will become black. So it is recommended to start with, after each use, it is recommended to wipe a paper towel, so that a small amount of sweat can be evenly distributed on the body of the copper pen. After a long time, a protective layer will be formed. It is recommended to wipe with a little vegetable oil (soybean oil, blending oil and peanut oil) every month. Package included: 1x brass straight ruler