Schwarzkopf BC Bonacure Fibre Force Fortifying Sealer (150ml) is an intensive strengthening leave-in milk that creates bonds inside the matrix to strengthen the hair fibres. It seals the hair cuticles and creates a protective shield around the fibre. It does this by utilising it's patented Bond Connector Technology which deeply reconstructs and seals each individual hair strand restoring it to virgin hair quality whilst simultaneously making it 10x more resistance to breakage. The result is noticeably stronger and glossier locks!