Schwarzkopf Professional Bonacure Keratin Smooth Perfect Treatment 200ml. The Schwarzkopf Bonacure Keratin Smooth Perfect Treatment is an intensive treatment mask that smoothes and cares for unruly, brittle and unmanageable hair. It is enriched with Keratin Smooth Technology and formulated with a combination of highly concentrated cationic polymers and silicone oils to deliver long-lasting smoothness, protection against humidity and a mirror-like shine. Cell Perfector Technology intensively repairs the internal hair structure and smoothes the hair's surface by depositing care agents on rough areas for an anti-frizz effect, significantly improving manageability and adding an intensive shine.