Item Type: Aperture Gauge_x000D_ Material: Stainless Steel_x000D_ Measuring Range: Approx. 1-6.5mm / 0.04-0.26in_x000D_ Accuracy: 0.1mm 1[MAIN PURPOSE] The aperture gauge is mainly used to measure the inner hole of thin walled parts, the inner diameter of plastic pipes, etc. 2[MEASURING RANGE] The measuring range is 1?6.5mm, with 0.1mm division value, has high efficiency and accuracy. 3[STAINLESS STEEL] Made of excellent stainless steel material, hard and wear resistant, not easy to rust or corrode. 4[LASER SCALE] There is laser engraved numeral scale on the cone surface, which can clearly observe the readings. 5[SIMPLE STRUCTURE] The taper aperture gauge structure is simple and reasonable, and the measurement is convenient and quick.1 x Aperture Gauge