Nanjing magnetic digital library card, materials, cards, Nanjing warehouse signs, magnetic label cards, signs --13,770,623,753 / 02585561575 / 025 833 64721 / 13382761736 / 13382002183 by the ABS engineering plastic widely used in institutions, military units, enterprises and institutions of the warehouse management. It is the back of the unique magnetic materials, can be directly adsorbed on the shelf, the lower the amount of recorded database to a turntable, the specifications are A, B, C, D, E, F, G, H, etc., can make it directly adsorbed iron shelf, on the first part of the inserted card, recording material name, size, type, lower portion of the dial shows the number of stocks, dial a location, there are A, B type, C type, D type, E type, F type, G type, H, K,, E-type can directly record storage, a library, inventory, certification for business, upgrade, the first class. The product is all over the country by the power supply bureau, power plants, oil refineries, steel mills, paper mills, electronics companies, machinery manufacturing, water companies and other units with favorable results.