{"product_id":"masterseal-np1-stone-10-1oz-polyurethane-sealant-pack-flexible","title":"MasterSeal NP1 Stone 10.1oz Polyurethane Sealant Pack - Flexible","description":"\u003cp\u003eIn this review of MasterSeal NP1 Stone 10.1oz polyurethane sealant pack, the bottom line is simple: it is aimed at contractors and serious DIYers who need a flexible, weather-resistant joint sealant that bonds without a primer. The reviewer found the product most valuable for joints that require movement accommodation and occasional water exposure, and for projects where acoustic performance matters. The pack includes enough tubes for multiple small-to-medium jobs and comes with AWF PRO gloves, making it convenient to apply while minimizing mess.\u003c\/p\u003e\u003ch2\u003eKey Features\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOne-component polyurethane:\u003c\/strong\u003e Moisture cured formulation provides easy single-part application and strong adhesion to most construction materials without a primer.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlexible movement range:\u003c\/strong\u003e Elastomeric properties allow joint movement of +\/- 35%, making it suitable for thermal and structural cycles.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeather and water resistant:\u003c\/strong\u003e Resists aging and weathering and has documented performance for water immersion and wet areas.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAcoustic benefit:\u003c\/strong\u003e Can be used as an acoustical sealant to reduce sound transfer and support higher STC values in partition systems.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePaintable and coating compatible:\u003c\/strong\u003e Compatible with non-rigid coatings and can be painted after cure for a finished appearance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFire tested:\u003c\/strong\u003e UL Listed and passes a 4 hour, 4 in fire and hose stream test when used with appropriate backing materials.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWho It's For\u003c\/h2\u003e\u003cp\u003eThis product is best for commercial contractors, acoustic installers, and advanced DIY users who need a durable, flexible sealant for joints between 1\/4' and 1\/2' depth and who value primerless adhesion. It works well on concrete (including green concrete) and most construction substrates, and is a good fit where occasional water immersion or exposure to weather is expected.\u003c\/p\u003e\u003cp\u003eLess suitable are casual homeowners needing a simple caulk for trim or bathroom tile touchups in very small quantities, or users who require an instant tack-free finish - this is a moisture-cure polyurethane that requires proper ventilation and tooling time and may dry more slowly than some silicone-based alternatives.\u003c\/p\u003e\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eStrong adhesion to many substrates without a primer, simplifying preparation.\u003c\/li\u003e\n\u003cli\u003eHigh elasticity with +\/- 35% joint movement capability for long-term performance.\u003c\/li\u003e\n\u003cli\u003eDocumented water immersion suitability and resistance to aging and weathering.\u003c\/li\u003e\n\u003cli\u003eUseful as an acoustical sealant to help reduce sound transfer in partitions.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSome customers reported occasional tubes drying out, so storage and shelf management matter.\u003c\/li\u003e\n\u003cli\u003eAs a polyurethane, it requires curing time and tooling skill compared with ready-cure silicones.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eSpecifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct form\u003c\/td\u003e\n\u003ctd\u003eOne-component polyurethane sealant\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePack size\u003c\/td\u003e\n\u003ctd\u003e12 tubes of 10.1oz each\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eJoint movement capability\u003c\/td\u003e\n\u003ctd\u003e+\/- 35%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended joint depth\u003c\/td\u003e\n\u003ctd\u003eMinimum 1\/4' to maximum 1\/2'\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWater performance\u003c\/td\u003e\n\u003ctd\u003eSuitable for water immersion and wet areas\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePaintability\u003c\/td\u003e\n\u003ctd\u003eCompatible with non-rigid coatings and paintable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFire rating\u003c\/td\u003e\n\u003ctd\u003eUL Listed; passes 4 hour, 4 in fire and hose stream with backing\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eOur Verdict\u003c\/h2\u003e\u003cp\u003eMasterSeal NP1 Stone 10.1oz in the 12-pack offers a strong, flexible polyurethane solution for professionals and experienced DIY users who need primerless adhesion, good acoustic performance, and water resistance. It represents solid value when multiple joints or larger projects are required, but users should store tubes properly and allow cure time for best results.\u003c\/p\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eCan this be used on new concrete?\u003c\/strong\u003e\u003cbr\u003eYes, it can be used in green concrete applications and bonds well without a primer when applied per instructions.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs it paintable?\u003c\/strong\u003e\u003cbr\u003eYes, the cured sealant is compatible with non-rigid coatings and can be painted.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes it handle water exposure?\u003c\/strong\u003e\u003cbr\u003eYes, it has documented performance for water immersion and is suitable for wet areas.\u003c\/p\u003e","brand":"AWF PRO","offers":[{"title":"Default Title","offer_id":48263571013851,"sku":"B0D9C7HMM5","price":98.79,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/81tX2_iGwCL._SL1500_7bf9932e-2ee6-4c27-a35e-346e3232bd8d.jpg?v=1778287992","url":"https:\/\/gearmusthave.com\/products\/masterseal-np1-stone-10-1oz-polyurethane-sealant-pack-flexible","provider":"GearMustHave","version":"1.0","type":"link"}