1. The high-grade ballpoint pen has obvious trademark grades and model marks on the pen holder. There are also obvious grades, production date and “DA” mark on the tail of the refill (the “DA” mark is the first Chinese pinyin of the file. Combination of letters).
2. The refill of the metal tubing must be used. The ball of the pen must be made of cemented carbide-tungsten carbide ball. The writing performance is better than that of the general ballpoint pen. The ink poured into the refill must be made of fixed-point 424 pure blue ink. And 322 black ink. These two inks have the advantages of light fastness, water resistance and no penetration. A ballpoint pen filled with these two inks can be used for archival filing (including plastic tubing refills, but the color of the tubing must be a light yellow tubing).
3. On the packaging of the goods, there are signs and marks such as the brand name, model number, manufacturer name, place of origin and quality inspection certificate. Counterfeit and inferior goods, the ink in the refill is not the archive ink approved by the National Archives Bureau. There is no “DA” mark on the refill, there is no trademark grade, model, factory name, place of origin, and some are unlicensed pens smuggled in foreign countries. Core, assembled as an imported high-quality ballpoint pen.