These carbon fibre 100mm (3.9") digital vernier calipers from B-G Racing is a very versatile tool suitable for measuring internal and external dimensions as well as hole depths and thickness. The gauge will give accurate readings that can be displayed in metric or imperial units in a resolution of 0.01mm/0.001".Suitable for use at home, workshop or at a race trackEasy to read digital scale provides accurate, repeatable resultsLR44 battery is includedMeasurements can be displayed in imperial or metricThe body of the caliper measures 100mm making it ideal for measuring fittings in an engine bay that are in tight spaces when compared to a conventional caliper that measures 150mm in length. The gauge has a measuring range of 0 to 100mm (0 to 4").