... 3.Hardened and precision ground 4.Accuracy:0.01mm ES electronic edge finder with led and beep, apply to conductive workpiece ... and machine toolAt present,we have 3 kinds of E.S Optical Edge Finder,the size as below, Order No ... Holding BarLengthAccuracy0927.007201640.010927.008320927.0092098The relative pictures as below, E.S Electronic Optical Edge Finder