HSN Code 3911 refers to "Petroleum resins, coumarone-indene resins, polyterpenes, polysulphides, polysulphones and other polymers and prepolymers produced by chemical synthesis, n.e.s., in primary forms." This classification code is essential for identifying various synthetic polymers and resins for import/export purposes based on their chemical composition and intended applications. Common products under HSN Code 3911 include petroleum resins, coumarone-indene resins, polyterpenes, and polysulphides. Additionally, the GST rate for these polymers and prepolymers under this code supports accurate trade compliance.