Profile: Qingdao Double Dragon Industry Co., Ltd. offers a wide range of chemical products. We manufacture chemical items like silica gel series, molecular sieve and sodium silicate covering Type A (narrow pore) silica gel, Type B silica gel, Type C (wide pore) silica gel, column chromatography silica gel, beer stabilizer silica gel, and pet padding material silica gel. Molecular sieve covers specifications like 3A, 4A, 5A and 13X. Blue indicating silica gel is available in various specifications from 0.2 mm to 8 mm in granular or spherical form. We can also process blue indicating silica gel in various other specification as per the requirement of customers. Molecular sieve 3A is an alkali metal alumino-silicate. It is the potassium form of the type A crystal structure. Type 3A has an effective pore opening of about 3 angstroms (0.3 nm). This is large enough to allow moisture, but excludes molecules such as unsaturated hydrocarbons which can potentially form polymers, and this maximizes lifetime when dehydrating such molecules.