The Sealey DBG509 Dial Bore Gauge is supplied in a wooden storage case The Sealey DBG509 is a Dial Bore Gauge that will indicate the deviation from set size by up to 5mm with an accuracy of 0.01mm. The DBG509 features a precision mechanism with a ∅50mm dial and locking rotating bezel, offering an accurate method of measuring a bore or detecting a taper or ovality. Features: Supplied in wooden storage case Probe body, dial indicator, anvil and spacer rings are also included Will indicate the deviation from set size by up to 5mm with an accuracy of 0.01mm Precision mechanism with ∅50mm dial and locking rotating bezel, offering an accurate method of measuring a bore or detecting a taper or ovality Specification:  Model No: DBG509  Resolution: 0.01mm Dial Diameter: ∅50mm  Measuring Range: 35-50mm  Maximum Deviation Measurement, Gauge: 5mm  Maximum Deviation Measurement with Stem: 1mm