Top Secret Hair Building Fiber Refills – Undetectable Thickening (Auburn, Regular)

Refresh and extend your Top Secret Hair Building Kit

Upgrade your look with a refill that preserves the trusted color and texture of your Hair Building Fiber Kit. This refill bottle delivers more fibers per jar, helping you maintain a fuller, natural appearance over time. Designed for ease, the refill works with the kit’s updated double patented Precision Applicator, so you can keep applying with precision without interruption.

Natural, undetectable fullness

The keratin-based fibers blend with your real hair, creating a subtle, fuller look that helps reduce scalp visibility. Color-matched shades (including Auburn) are developed by a renowned hair expert to maintain a cohesive, natural appearance. The result is a refinement you can see and feel, without obvious signs of enhancement.

All-day coverage for real-life conditions

These fibers are formulated to stand up to wind, rain, and sweat, helping your style stay put throughout the day. They stay in place until you wash them out with your regular shampoo, offering a reliable option for busy days and active moments.

• Weather and sweat resistance helps maintain fullness during daily activities.
• Easy, targeted application with the updated Precision Applicator for precise coverage.

Whether you’re preparing for a work presentation, a social event, or a workout, you can expect a fuller look that remains natural and comfortable.

What’s included and how it works

This refill bottle extends the life of your kit while preserving the same high-quality fibers and application experience. The kit components are designed for convenience and portability, including a Precision Applicator with Protective Cap, a Sifter Top, a Travel Bag, a brochure, and a paper clip for quick setup on the go.

• Refill bottle to extend your existing hair-building routine.
• Works with the new double patented Precision Applicator for controlled coverage.
• Includes Sifter Top, Travel Bag, brochure, and paper clip for easy travel and use.

Ethics, care, and suitability

Top Secret fibers are vegan, cruelty-free, paraben-free, and hypoallergenic, offering an approachable option for many users seeking a fuller look without compromise.