A multi-component packaging unit for reductive decolouration of dyed keratinic fibers, which comprises, presented separately from one another, a container (A) containing a solid or powdered cosmetic agent (a) and a container (B) containing an aqueous cosmetic agent (b)； wherein the agent (a) in container (A) contains one or more sulfinic acid derivatives from a group as defined in claim 1； and wherein the total content of all metal salts contained in agent (a) from the group of magnesium, zinc, iron, copper and calcium salts is below 0.1 wt% and the total content of all metal salts contained in agent (b) from the group of magnesium, zinc, iron, copper and calcium salts is below 0.1 wt%. Preferably, the sulfinic acid derivative is formamidinesulfinic acid. Agent (b) is preferably alkaline in nature, having a pH of 7.5-12.0. Agent (b) may comprise alkalizing agents, e.g. monoethanolamine, triethanolamine, 2-amino-2-methyl-propanol, arginine, lysine and/or histidine. Also disclosed is a method for reductive decolourisation of colored keratin fibers using the multi-component packaging unit, comprising preparing a ready-to-use decolouring agent by mixing cosmetic agents (a) and (b). The multi-component packaging unit of the invention provides reductive removal of colour from dyed hair with minimal odour and re-colouration.
