Sodium Hydro Sulphite, also known as Sodium Dithionite, is a sulphur agent or reductive bleaching chemical that is used in the dyeing of vat, polyester, and indigo. Its also used as a non-aggressive alternative to bleach for removing colour from coloured materials and whiten old textiles. It has a sulphurous odour and is stable in the absence of air, but when exposed to hot water, it decomposes. During the production process, Sodium Hydro Sulphite has undergone various quality inspections to assure its quality and effectiveness, and it is available at very reasonable prices.