--- product_id: 14439147 title: "MasterSeal NP1 10.1 Oz. Polyurethane Sealant, Stone" brand: "masterseal np1" price: "124 zł" currency: PLN in_stock: true reviews_count: 8 category: "Master Seal Np1" url: https://www.desertcart.pl/products/14439147-masterseal-np1-10-1-oz-polyurethane-sealant-stone store_origin: PL region: Poland --- # 24-Hour Full Cure Time 100% Waterproof Seal 300 PSI Tensile Strength MasterSeal NP1 10.1 Oz. Polyurethane Sealant, Stone **Brand:** masterseal np1 **Price:** 124 zł **Availability:** ✅ In Stock ## Summary > 💪 Seal Strong, Stay Dry — Master the Art of Waterproofing! ## Quick Answers - **What is this?** MasterSeal NP1 10.1 Oz. Polyurethane Sealant, Stone by masterseal np1 - **How much does it cost?** 124 zł with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pl](https://www.desertcart.pl/products/14439147-masterseal-np1-10-1-oz-polyurethane-sealant-stone) ## Best For - masterseal np1 enthusiasts ## Why This Product - Trusted masterseal np1 brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Powerful Elasticity:** Permanent flexibility adapts to expansion and contraction without cracking or losing adhesion. - • **Ready-to-Use Convenience:** One-component, gun-grade formula requires no mixing or priming for fast, hassle-free application. - • **Ultimate Waterproof Defense:** Seals active joints on floors, walls, and structural components to keep moisture out and your space dry. - • **Versatile Surface Compatibility:** Bonds seamlessly to concrete, masonry, aluminum, wood, and more for professional-grade results. - • **Precision Control for Detail-Oriented Pros:** Thick consistency allows shaping and angled finishes, perfect for meticulous projects. ## Overview MasterSeal NP1 is a high-performance, one-component polyurethane sealant designed for durable, waterproof sealing on a variety of substrates including concrete, masonry, and metal. With 300 PSI tensile strength and a 24-hour cure time, it offers permanent elasticity and excellent adhesion without priming, making it ideal for both interior and exterior joints in demanding environments. ## Description MasterSeal NP 1 is a one-component, high-performance, non-priming, gun-grade, elastomeric polyurethane sealant. It requires no mixing and typically requires no priming to bond to many materials, including concrete and masonry. Review: Great, with a caveat - I have used this twice. First, I installed a modern awning above an exterior door and to prevent water coming through the small gap between the awning and the wall it was attached to, I used this sealant. It worked great! It completely stopped rain from running down the door. So I tried it again. This time to fill the gaps between a flat linear shower drain and the tiles surrounding it. Again, it sealed the area completely and water from the shower now flows down the drain with no issues . Before, some water was going into the crevices left by the tile installer. Problem is, as other reviewers stated, the material is thick and requires some prep work in order to achieve a clean outcome. Yes, have lots of paper tissue or rugs available. You will be cleaning your hands/fingers all the time. Yes, have blades from a utility knife available to clean any excess. Don't forget to use painter's tape to protect the areas you don't want to have this sticky material on. And, specially, work slowly. Be patient. The thick material is not entirely a bad thing. It will allow you to shape things as you need/want. I required a 45 degree angle for the water to flow from the shower flow into the flat linear shower drain and the thickness made it easier. If you are a detailed-oriented person, you are going to like this product. Review: Great sealent - Water was getting into my basement. I used this between my foundation wall and sidewalk. There was about a quarter inch gap between the two. It stopped the water from seeping between. My basement is now dry. It has last at least two seasons. WARNING: It is thick! At first I thought it was all dried up. No, it was just that tick. You will have to have very strong hands to squeeze the caulking gun. But it is worth it. ## Features - MasterSeal NP1 10.1 Oz. Polyurethane Sealant, Stone - A versatile moisture-curing high-performance polyurethane sealant with permanent elasticity (Formerly: Sonolastic NP 1). - or use on active, vertical and horizontal interior, exterior joints including expansion wall joints, floor and pavement joints, curtain walls, panel walls, precast walls, - window frames, structural components, dams, spillways, and storm water drains. Substrates include concrete, masonry, aluminum, and wood. - Pack of 1 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00UMWTB8I | | Best Sellers Rank | #45,258 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #146 in Adhesive Caulk | | Brand Name | MasterSeal NP1 | | Color | Stone | | Customer Reviews | 4.5 4.5 out of 5 stars (191) | | Full Cure Time | 24 Hours | | Item Form | Liquid | | Item Weight | 10.1 Ounces | | Liquid Volume | 10.1 Fluid Ounces | | Manufacturer | BASF | | Material Type | Polyurethane | | Number of Items | 1 | | Part Number | NP1STONE | | Surface Recommendation | Floor,Wall,Walls,Window | | Tensile Strength | 300 Pounds Per Square Inch | | Unit Count | 1.0 Count | | Water Resistance Level | Waterproof | ## Product Details - **Brand:** MasterSeal NP1 - **Color:** Stone - **Full Cure Time:** 24 Hours - **Item Weight:** 10.1 Ounces - **Liquid Volume:** 10.1 Fluid Ounces ## Images ![MasterSeal NP1 10.1 Oz. Polyurethane Sealant, Stone - Image 1](https://m.media-amazon.com/images/I/31duoo2CfqL.jpg) ## Questions & Answers **Q: what does 'stone' mean? color? or material its used on?** A: Stone is the color of the caulk. I used it in my pool where the copping joined the top row of tiles. It matched the color in the copping. You can purchase it in colors other than "stone." Hope this helps. **Q: If left unpainted, does this sealant tend to attract dirt outdoors, or does it stay clean and white?** A: Clean and white. **Q: Is this product heat resistant?** A: It is made for outside use and I have used it to seal around replacement windows. I don't see anything on the label that specifies its heat resistance. **Q: can i use this to fill gaps in my stone fireplace mantle and then paint it ?** A: Very good product for stone, this is not for beginners Very sticky, not shire what heat temperatures are ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great, with a caveat *by R***D on August 4, 2023* I have used this twice. First, I installed a modern awning above an exterior door and to prevent water coming through the small gap between the awning and the wall it was attached to, I used this sealant. It worked great! It completely stopped rain from running down the door. So I tried it again. This time to fill the gaps between a flat linear shower drain and the tiles surrounding it. Again, it sealed the area completely and water from the shower now flows down the drain with no issues . Before, some water was going into the crevices left by the tile installer. Problem is, as other reviewers stated, the material is thick and requires some prep work in order to achieve a clean outcome. Yes, have lots of paper tissue or rugs available. You will be cleaning your hands/fingers all the time. Yes, have blades from a utility knife available to clean any excess. Don't forget to use painter's tape to protect the areas you don't want to have this sticky material on. And, specially, work slowly. Be patient. The thick material is not entirely a bad thing. It will allow you to shape things as you need/want. I required a 45 degree angle for the water to flow from the shower flow into the flat linear shower drain and the thickness made it easier. If you are a detailed-oriented person, you are going to like this product. ### ⭐⭐⭐⭐⭐ Great sealent *by B***S on June 24, 2025* Water was getting into my basement. I used this between my foundation wall and sidewalk. There was about a quarter inch gap between the two. It stopped the water from seeping between. My basement is now dry. It has last at least two seasons. WARNING: It is thick! At first I thought it was all dried up. No, it was just that tick. You will have to have very strong hands to squeeze the caulking gun. But it is worth it. ### ⭐⭐⭐⭐⭐ It stinks, but it works *by L***H on December 5, 2023* This is a great product. Nothing gets through it. It stinks, and needs a while to dry, but it works. --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.pl/products/14439147-masterseal-np1-10-1-oz-polyurethane-sealant-stone](https://www.desertcart.pl/products/14439147-masterseal-np1-10-1-oz-polyurethane-sealant-stone) --- *Product available on Desertcart Poland* *Store origin: PL* *Last updated: 2026-05-08*