The maintenance room of the measuring block must keep a clean side of dust to prevent the measuring block from being scratched by dust on the surface of the measured object. Before using the measuring block, you need to wipe the absorbent cotton ball on the surface of the measuring block. During use, the user must wear a mask to prevent spitting from splashing on the measuring block when talking, which will cause rust. After use, wash and coat oil. In normal times, if the gauge block is not in use, it is also necessary to strengthen the maintenance. Periodically, wash and apply sunscreen. When it is not used for a long time, thoroughly scrub and oil at regular intervals. When storing the gauge blocks, they should be neatly aligned and placed side by side in the deep device, and can not be placed at will, so as to avoid collisions and create gaps. Even if scratches occur, they must not be sanded. Remember not to touch the measuring block directly with your hands, to avoid sweat left on the measuring block, which will cause the measuring block to corrode the accuracy of the image measurement.