GST classification dictates applicable tax rates and levy treatment, including reverse charge and NCCD implications. Classification and applicable GST rates are specified for a range of goods by reference to HSN headings, with operative tax consequences tied to those classifications. The guidance notes reverse charge on raw cotton supplied by an agriculturist to a registered person, differential treatment by technical characteristics (such as fibre decitex and preservation state), exemptions or no refund of unutilised input tax credit for certain items, and the continued levy and Central Excise valuation of National Calamity Contingent Duty (NCCD) on tobacco products.