Best suited to fine-to-medium hair that is damaged, brittle, or over-processed from color services or heat styling and needs repair benefits without added weight. Works as a leave-in step for people who want body and frizz control alongside bond repair, rather than a heavy, rinse-out mask; suitable for both salon and at-home retail use.

Its differentiator is doing double duty as both a bond-repair treatment and a styling step, so damaged hair gets structural repair benefits without stacking on a separate deep-conditioning mask before every blow-dry — useful for people maintaining color or heat-damaged hair on an ongoing basis rather than just occasionally.

1. Shampoo and rinse hair thoroughly, then towel-dry to remove excess water.
2. Shake the bottle well before use.
3. Spray evenly onto damp hair from about 6 inches (15 cm) away, working from roots to ends.
4. Do not rinse out — blow-dry and style as usual to activate the bonding ingredients.
5. Use weekly, or more often on hair that is especially stressed or brittle.

Pros:

• Combines bond-building repair and lightweight styling support in one leave-in step, without rinsing
• Malic-acid-based chemistry targets internal bond damage rather than just coating the hair surface
• Sebastian's own testing supports up to 99% less breakage versus a low-conditioning shampoo, as part of the No.Breaker system
• Weightless enough for fine-to-medium hair that can't tolerate a heavy leave-in mask

Cons:

• Contains isopropyl alcohol and several fragrance allergens (hexyl cinnamal, linalool, geraniol, benzyl salicylate), worth noting for sensitive scalps
• The 99% breakage figure is a system-level claim (measured against a low-conditioning shampoo) rather than a guaranteed standalone result from this product alone
• Meant for damp hair before styling, not as a standalone leave-in on fully dry hair