This is a high precision ABSOLUTE Digital Height Gauge that offers you thefollowing benefits:It has a high accuracy, high resolution ABSOLUTE linear encoder forposition detection.Types with and without pneumatic drive mechanism.Automatic running of prelearnt part programs.You can easily implement frequently used measurements, such as inside/outside diameter and pitch calculations, by icon-based commands that also support easy one-key operation.Extraordinary battery life.GO/±NG judgement is performed by setting the upper and lower tolerances.