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    ISDIN

    ISDIN Si-Nails - Fast Absorbing Nail Strengthening and Hardening Serum for Nail Durability in Thin Nails, made with Cationic Hyaluronic Acid 0.08 FL OZ

      • Based on 2,166 reviews
    Condition: New
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    $29.25 Why this price?
    Save $9.75 was $39.00

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    As low as $7 / mo
    • – 4-month term
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    Non-returnable. Transportation of this item is subject to hazardous materials regulation

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    Availability: In Stock.
    Fulfilled by Amazon
    Arrives Wednesday, May 14
    Order within 22 hours and 43 minutes
    Available payment plans shown during checkout

    Brand: ISDIN


    Item Form: Gel


    Specialty: Strengthener


    Number of Items: 1


    Unit Count: 1 Count


    Is Discontinued By Manufacturer ‏ : ‎ No


    Product Dimensions ‏ : ‎ 1.61 x 1.14 x 5.67 inches; 0.32 ounces


    Country of Origin ‏ : ‎ Spain


    Frequently asked questions

    If you place your order now, the estimated arrival date for this product is: Wednesday, May 14

    This item is non-returnable:

    Non-returnable. Transportation of this item is subject to hazardous materials regulation

    View our full returns policy here.

    • Klarna Financing
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    • Financing through Apple Pay
    Leasing options through Acima may also be available during checkout.

    Learn more about financing & leasing here.

    Similar Products

    Top Amazon Reviews

      • Really truly works
    Review Image by GdF GdF
    Life changing (at least for my nails LOL). I never leave reviews but this is too good not to share. Disclaimer: I'm a nail nut. A few years ago, at the age of 53, I decided I was very tired of brittle, flaky, dry, weak nails. I have always taken care of my nails, so the changes I was seeing were age related. I was eating healthy and exercising, was using nail polish but never gel, I moisturized etc. Nothing was helping. I used a special nail oil 6-8 times a day and no acetone and no nail polish for A YEAR and saw very little improvement. Then I discovered Dr Dana's Deep Hydrading Formula and saw an immediate improvement using their Deep Hydrating Formula...again I applied it on average 6 times a day so definitely was committed. My nails stayed short but stopped splitting and chipping...that was after about a month of use. They also have a hyaluronic serum but recommend using once a week. Then I discovered this product and went nuts with it. I bought three applicators, kept one by my desk, one in my bathroom and one in my car. I probably apply it 12 times a day LOL...certainly after any time I was my hands. It's easy. I apply a top 'coat' of the Dr Dana Formula after using the SI-NAILS. This is the magical combo. My nails are strong, flexible, and growing. This is the best they've looked in 20 years. So if you are unhinged like me and willing to go the distance, the combo of these two products changed my nails, they look 30 years younger ;) ... show more
    Reviewed in the United States on April 11, 2025 by GdF GdF
      • It Works!!!!
    It works! I've tried so many products that were "supposed" to strengthen my nails so I was skeptical. I went to a new nail salon and they drilled my already thin nails into nothing. My nail beds were tender for 2 weeks. I was looking for ANYTHING that might help. I read the reviews and decided to give it a try. After the first week, I noticed my nails were definitely stronger. I've been using for 2 weeks now and I've been amazed. This stuff is the real deal! ... show more
    Reviewed in the United States on April 11, 2025 by Kindle Customer
      • Leaks. Ran dry in under 2 weeks.
    Couldn't test if the claims that this product improved nails in as little as a month, as it ran dry in less than half that time. It was only turned tip down when in use. It was certainly never stored in that position. At first, it was stored laying on it's side on my bedside tray between uses. It did not leak while the cap was closed, but I quickly became concerned that product was being wasted when so much poured out the moment I removed the cap. I switched to storing it tip facing up in a small pencil box. After the change, no product poured out just by removing the cap. The instructions tell you to pump once for EACH nail. I never had to pump more once for ALL of them, and often there was still more than my nails could even absorb. For the first week. After that, there was considerably less. It has now been less than 2 weeks it and it is completely dry. It might be a good product in poor packaging?? Couldn't use it long enough to find out. It is of course possible I just got a dud. But I'm not willing to shell out another $29 to find out. Very disappointing. ... show more
    Reviewed in the United States on July 4, 2023 by DD
      • Really works!
    I’ve been using this off and on for about 2 months and have noticed a difference on my brittle, peeling nails. I’ve tried dozens of different products and nothing else has helped. I’ve put this on my bare nails 3-4 times a week at night (when I wasn’t wearing nail polish) and it has drastically reduced the peeling and cracking that has taken over my nails as I’ve gotten older. It is pretty expensive but I’m on the same tube 2 months later so it’s definitely worth a try! ... show more
    Reviewed in the United States on March 29, 2025 by AP
      • Amazing results!
    Review Image by Letty Graff Letty Graff
    Review Image by Letty Graff Letty Graff
    Review Image by Letty Graff Letty Graff
    This stuff was literally an answer to prayer! HIGHLY RECOMMEND! I had been struggling with thin, peeling nails for over a year. I had back-to-back surgeries and my dermatologist told me my damaged nails were probably a result of the anesthesia. (I've never done regular manicures and very rarely polish or gel, so I couldn't blame that.) My nails were so thin they hurt and they would continually split and peel no matter how much I used nail strengthening treatments or polishes. I was at my wits end and tried ordering ISDIN as a last resort. I thought it was a little expensive at the time, but now I believe it was worth every penny! I keep an extra tube on hand now so I never run out. The product and brush are so easy to use. In the beginning I applied it twice a day but tried to keep using it at least once a day for two months. Now that my nails have improved I use it about every 1-2 days. The product is easy to apply and dries and disappears very quickly. I was worried it would be messy and sticky but it is not at all. Sometimes it takes one click per nail to get it going, but sometimes one click will treat a few fingers. A little goes a long way and you will get the feel of it. The product does take time to work. It was 2 months before I had a complete nail grow out without peeling. They are strong now but I am still careful to not use my nails as "tools" so that I don't break them. I still have a split on my thumbnail but I believe it will grow out as long as I am careful and keep applying the product every few days. I will say my nails are a little "ridged" and I don't know if that's just my nails or a result of the product, but it is a small price to pay for strong nails and I can just buff them down smooth. The photos you see are: 1. at the beginning of use, 2. after 6 weeks of using the product, and 3. at 2 1/2 months (they do grow longer but I like to keep them short) Don't hesitate! Buy this product! ... show more
    Reviewed in the United States on June 4, 2024 by Letty Graff Letty Graff
      • Stopped working after 4 days
    I really, really liked this product, but it only lasted 4 days. In retrospect, I think I received a used or defective product. I only had to click it about 3 times the first time I used it. It worked well for the first 4 days, then completely stopped dispensing the liquid. It made my nails feel strong. I used it twice a day and followed the directions for one click per nail, which worked nicely. I bought it to use when recovering from a surgery because I knew I had to sit still for a few weeks and would be able to go without nail polish. My surgery was rescheduled for a few weeks later, so I didn’t even open it until it was too late to return it. I left seller feedback, but have not received a response. I will likely buy it again directly from ISDIN instead of Amazon. ... show more
    Reviewed in the United States on May 30, 2023 by birdsrk

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