This excellent electronic optical edge finder quickly locates working edges and saves time when finding positions on milling machines, jig drills, etc. Hardened and precision ground, there is no need to rotate during measurement; the sensor is spring-loaded to prevent accidental damage from overun. The LED lights up instantly and beeps when Pro-BE touches the conductive workpiece, stronger and brighter. Shank diameter: 20 mm, Pro-BE diameter: 10 mm, accuracy: 0.005 MM. Suitable for traditional milling machines and integrated processing machines. Package includes: 1x Electronic edge finder(Battery not included) 1x wooden case Specifications Product color: Silver Material: stainless steel Box size: 200 x 60 x 35 mm/7.87 x 2.36 x 1.37 in. x 2.36 x 1.37 in. Finder length: 160 mm/6.3 in. Stem diameter: 20 mm/0.8 in. Pro-be diameter: 10 mm/0.4 in. Note: Please allow 1-3 cm error due to manual measurement. Don't mind before you buy. Due to the difference between different monitors, the picture may not reflect the actual colour of the item.