BMD high-precision plug gauge measuring head is suitable for automatic and manual measurement in mass production. Its unique guiding cylinder design ensures the reliability of measurement results, solves the centering problem of aperture measurement, minimizes the influence of human factors on the measurement results, and can be convenient, stable and accurate measurement. BMD probe can not only accurately measure aperture, but also measure various geometric errors. Such as through hole, blind hole, cone hole, step hole, square hole and other holes. The customer needs to provide the following parameters to select the plug gauge: aperture (with tolerance), through hole or blind hole, hole material, hole depth, if there is a drawing is best.