Probe Diameter: 0.394in/10mm, Shank Diameter: 0.787in/20mm, Overall Length: 6.299in/160mm, Repeatability: 0.00079in/0.02mm T.I.R. (Please check the required size before purchasing, this is the metric standard.) Battery: 2pcs 1.5V; Model: LR1/1.5v/N( high: approx 1.22in/31mm, outer diameter: approx 0.45in/11.5mm). (The battery is not include) Included: 1 x Electronic edge finder with original box, for easy carrying and storage. (The battery is not include) Practicality: This photoelectric mechanical edge finder can measure the X and Y axis coordinates of the workpiece. Not Necessary to Rotate While Measuring Feature: This product employ a highly sensitive location sensor and utilise a red pilot light which can be clearly seen, beep louder