The measuring bar of this depth caliper has a hook. Both sides of the hook can be used as a measuring surface. This means that the depth gauge can be used for normal depth measurement as well as for measuring grooves, recesses and shoulders. Technical details of the digital depth caliper Measuring range 0-150 mm / 6 inches Error limits 0.03 mm Digit step value 0.01 mm / 0.0005 inch Width of the hook 2 mm Unit of measurement switchable mm/inch Zero adjustment at any position Data output