1.表圈轉(zhuǎn)動圈為金屬外圈 Adjustable steel dial ring. 2.量桿上部為隨動于量桿的防塵帽 Anti-dirty screw rises while lifting measuring spindle. 3.帶公差指示器 With adjustable tolerance markers. 4.帶表圈緊固裝置 With dial locking screw.