Manucurist Duo Day & Night Nail Strengthener Kit - 10% Keratin Booster & Overnight S.O.S. Mask for Fragile Nails

Manucurist Duo Day & Night Nail Strengthener Care Kit pairs a 10% keratin concentrated serum for daytime strengthening with an overnight S.O.S. nail mask to nourish and help restore fragile nails.

This two-step express routine combines targeted daytime reinforcement and deep overnight hydration to address soft, weakened or splitting nails. Developed in France with plant-based keratin and supportive actives, the kit is designed to harden and revitalize nails through a simple daily application: a Keratin Booster for daytime repair and an S.O.S. Nail Mask for restorative nights.

How does the Keratin Booster support nail strength during the day?

The Keratin Booster is a concentrated nail hardener serum formulated with 10% keratin to reinforce and thicken the nail plate. It also includes gentle exfoliating acids and strengthening co-actives aimed at reducing brittleness and improving resistance to splitting.

• 10% plant-based keratin concentrate to fortify the nail structure
• AHA and gluconolactone for mild nail plate renewal
• Silicon and biotin to support improved nail resilience
• Easy brush-on application for 1–3 times daily use on bare nails

What does the S.O.S. Nail Mask do overnight and how is it used?

The overnight S.O.S. Nail Mask delivers intensive hydration and creates a protective film that helps nails retain moisture while you sleep. Apply a thicker layer two to three nights per week, allow it to dry, then remove by peeling or washing off the following morning.

• Thick, film-forming overnight application for deep hydration
• Use 2–3 nights weekly on clean, bare nails
• Removes easily by peeling or with soapy water the next morning
• Clinical panel results indicated improved hydration and perceived strength

How do I combine the day and night steps into a routine?

Use the Keratin Booster throughout the day on bare nails to build strength and reduce splitting, and reserve the S.O.S. Mask for targeted overnight recovery sessions. For best results, add daily cuticle nourishment as a finishing touch to maintain healthy surrounding skin.

• Day: brush Keratin Booster on clean nails 1–3 times daily, let absorb
• Night: apply a thick S.O.S. Mask 2–3 nights weekly, remove in the morning
• Pro tip: pair with a cuticle nourishing pen for daily hydration
• Consistent short-term use showed measurable improvement in panel studies

Who is this for? The Manucurist Duo Day & Night Nail Strengthener Care Kit is made for anyone with soft, fragile or damaged-looking nails who wants a simple, time-efficient routine. It suits people seeking plant-forward, vegan-friendly nail care developed in France, and those who prefer separate day and night treatments rather than a single all-in-one product. Ideal for users looking to strengthen nails, reduce splitting, and add restorative hydration without heavy salon treatments.

Manufactured with a focus on cleaner formulas, the set is easy to incorporate into daily life: daytime reinforcement with a keratin-rich serum, plus an intensive overnight mask for recovery. While results vary by individual, short clinical panels reported high rates of perceived improvement in hardness, strength and hydration within about two weeks of following the regimen.