Killys 3-in-1 Hardener Hypoallergenic is an advanced nail treatment designed to strengthen, protect, and smooth fragile nails. With its gentle hypoallergenic formula, it reinforces nail structure, prevents breakage, and enhances resilience without causing irritation. Acting as a treatment, protective layer, and base coat in one, it delivers healthier, shinier, and more durable nails while being safe for sensitive users.