Accurately measure seat posts head tubes bearings spoke diameters & just about anything else you can think of The DC-1 is a precision made instrument built with stainless steel mechanisms & a rugged ABS composite body An indispensable shop tool able to measure in inch fractions as well as metric & decimal standard Features include: Large LCD display Display in metric decimal standard & fractional standard to 1/128 inch Measures external internal depth & stepped dimensions Resolution: +/- 0.01 mm / 0.0005 inch / 1/128 inch Accuracy: +/- 0.02 mm / 0.001 (-100 mm) Repeatability: +/- 0.01 mm/0.0005 inch Protective case & battery included