https://i0.wp.com/gstindiaupdates.com/wp-content/uploads/2016/11/gst.jpg?resize=480%2C320HSN (Harmonised System of Nomenclature) is an internationally accepted product coding system formulated under General Agreement on Tariffs and Trade (GATT). In India, currently, adapted HSN coding is currently used under Excise and Customs for classification of products.