K18 Molecular Repair Hair Oil - 1 fl oz Lightweight Peptide Strengthening Oil for Frizz Control & Heat Protection

K18 Molecular Repair Hair Oil is a lightweight, peptide-powered treatment oil designed to strengthen hair, smooth frizz, and add long-lasting shine without silicone or heaviness.

This biotech-formulated oil blends K18's patented peptide technology with nourishing plant oils to act at two levels of the strand: it targets inner-fiber damage while also smoothing the cuticle surface. The result is manageable, shinier-looking hair that resists frizz and styling stress. The 1 fl oz bottle delivers a versatile leave-in treatment suitable for daily finishing or as a follow-up to K18's Molecular Repair Hair Mask.

How does K18 Molecular Repair Hair Oil reduce frizz and strengthen hair?

The oil combines a strengthening peptide system with emollients that smooth the hair's outer layer. The peptide works on inner-fiber weaknesses while the oil components sit on the cuticle to reduce surface roughness, which helps strands lie flatter and reflect light better.

• Peptide technology targets internal fiber structure to improve resilience.
• Avocado, sunflower oils and squalanes smooth and hydrate the cuticle.
• Silicone-free, weightless feel avoids buildup that can weigh hair down.

Can this oil protect my hair during heat styling up to 450°F?

Yes — the formula includes heat-styling protection designed to shield strands during high-temperature styling. Use a small amount before blow-drying or thermal tools to help limit the additional damage that can cause frizz and split ends.

• Apply to damp hair before blow-drying for protection and manageability.
• Works as a finishing oil on dry hair to smooth and elevate shine.
• Helps reduce visible split ends when used as part of a consistent routine.

How much should I use and how do I add it into my routine?

Start conservatively — 1–3 drops — and increase slightly for thicker or coarser hair. Apply from mid-lengths to ends on towel-dried hair after cleansing, or use a drop or two on dry hair to tame flyaways and add gloss. It pairs well after intensive repair treatments like the K18 Molecular Repair Hair Mask.

• 1–3 drops for fine or short hair; more for long or coarse textures.
• Apply to damp hair for repair or dry hair for finishing and shine.
• Layer after leave-in repairs for comprehensive strengthening and smoothing.

What visible improvements can I expect and how quickly?

Users generally notice smoother, shinier hair and easier styling after initial use, with cumulative improvements in manageability over continued use. The oil is formulated to enhance color vibrancy and shine while helping reduce the look of split ends when incorporated into a regular hair care routine.

• Immediate surface smoothing and increased light reflection for shine.
• Progressively improved strength and manageability with repeated use.
• Designed to avoid residue, preserving bounce and movement.

Who is this for: K18 Molecular Repair Hair Oil is aimed at anyone looking to repair and manage frizz-prone, heat-styled, or chemically treated hair without a heavy silicone finish. It suits all hair types that need a weightless boost in shine, protection during styling, and support for reducing split-end appearance when used consistently as part of a repair-focused routine.

Ingredients

Caprylyl Caprylate/Caprate, Squalane, Persea Gratissima (Avocado) Oil, Helianthus Annuus (Sunflower) Oil, C13-15 Alkane, Undecane, Benzyl Alcohol, Tridecane, Castor Isostearate Succinate, Propanediol, sh-Oligopeptide-78, Fragrance (Parfum), Tocopherol, Cinnamal, Hexyl Cinnamal, Limonene, Linalool.