Professional tool for commercial or occasional use Precision made Vernier slide calliper. -Carbon fibre construction so lightweight to use but still strong enough to last -Can measure internal and external sizes. -Also can measure hole/tread depth with the built in depth stop. -A simple way to make accurate measurements of internal and external distances of up to 150mm. -Comes in a sturdy plastic case for protection when not in use. -Includes depth measuring tool. -Can display in Metric or SAE (imperial sizes). -Measuring Range 0150mm (06") -Accuracy plus or minus 0.02mm (0100mm range) and plus or minus 0.03mm (100mm plus range) -Accuracy is also effected in areas of very high humidity (over 80%).