1. Measuring range The measuring range is 50 100 mm, with an accuracy of 0.0005 mm, offering precision. It is suitable for comparative measurement of workpiece inner diameters and machining measurements. 2. Tip contact points The dial bore gauge features tip contacts for extended wear, improved abrasion resistance, and a long service life. It has been widely used by professionals, hobbyists, jewelers, and woodworkers. 3. Easy to use The bore measurement process is streamlined for ease and precision. Simply adjust the dial display pointer to zero before measuring to ensure unparalleled accuracy every time. 4. 11 pieces Includes 11 measuring needles to meet most of your inner diameter measurement needs. Multiple measurement modes provide versatility for various usage scenarios, making the measurement process convenient.