- Vernier Interpupillary Distance Ruler: Made from durable PVC, this ruler measures pupil distance (PD) from 0 to 100mm, making it an essential tool for purchasing glasses online. - User-Friendly Design: Simply position the notch at the bridge of your nose, as close to your eyes as possible, and find the center between your pupils using a mirror. Quickly read the nearest line to achieve an accurate measurement. - Ergonomic and Versatile: Designed for comfort and sensitivity, the thick double-layer glass ensures durability and clear visibility. The ruler allows for smooth adjustments, offering versatility for various measurement needs. - High Precision: Experience exceptional accuracy with easy reading capabilities, delivering precise measurements with minimal error for optimal results. Use Cases: 1. Ideal for online eyewear shopping, ensuring you select the perfect frame that fits your unique measurements. 2. Perfect for opticians and eye care professionals needing accurate PD measurements to provide clients with the correct lens alignment. 3. Useful for individuals conducting vision tests at home, enabling them to understand their vision needs before consulting with a professional. This vernier interpupillary distance ruler combines high functionality with user convenience, ensuring reliable results every time.