Made of plastic materials, distance ruler is resistant to damage, don't have to worry about long-term use. At the same time, it is compact and lightweight, making it easy to carry around without taking up too much space. This pupillary distance ruler is a must-have tool for your eye health. This is a must-have tool to make your eyeglass more secure. Features -Color:As shown -Material:Plastic -Size:18.00X3.50X0.20cm/7.07X1.38X0.08in -Advanced measurement technology enables high precision measurement results. -Make your eyeglass more scientific and avoid the discomfort caused by wrong optometrist. -Provide suitable measurement for different age groups and types of glasses. Better meet the needs of different eyeglass. -Make your visual experience better and avoid the trouble caused by inaccurate optometrist. -An important tools for optical industry, providing convenient support for dispensing opticians. Package list: 5 x Pupillary Rulers