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    Sikaflex® NP 1 (formerly known as MasterSeal® NP 1)

    One-component, elastomeric, gun-grade polyurethane sealant

    Formerly: Sonolastic NP 1

    How does MasterSeal NP 1 work?

    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.

    Recommended uses:

    • Interior and exterior
    • Above and below grade
    • Immersed in water
    • Expansion joints
    • Panel walls
    • Precast units
    • Aluminum and wood window frames
    • Roofing
    • Fascia
    • Parapets
    • Vinyl siding
    • Store front assemblies

    What are the unique features of MasterSeal NP 1?

    • Available in ProPaks, reducing jobsite waste, lowering disposal costs
    • 12 standard colors to match a wide variety of common substrates
    • Wide temperature application range makes MasterSeal NP 1 suitable for all climates
    • UL listed; Passes 4–hour, 4–inch, fire and hose stream test when used with Ultra Block or mineral wool
    • Suitable for water immersion with documented performance in wet areas
    • Meets VOC requirements in all 50 states

    What are the benefits of MasterSeal NP 1?

    • One-component formula requires no mixing, helping to reduce labor costs
    • Joint movement capability ±35% provides excellent flexibility for keeping moving joints weathertight
    • Easy to gun and tool, speeding up application and making neater joints
    • No primer required for most construction materials lowering installation costs
    • Weather resistant for long-lasting weather tight seals
    • Compatible with non-rigid coatings and can be painted
    • Superior holding power for long-lasting roof tile installation

    Product Information

    Data Guide

    Certification Letter

    LEED v4 Letter

    Safety Data Sheets - Aluminum Gray

    Safety Data Sheets - Limestone

    Safety Data Sheets - Medium Bronze

    Safety Data Sheets - Off White

    Safety Data Sheets - Off White (Propack)

    Safety Data Sheets - Redwood Tan

    Safety Data Sheets - Special Bronze

    Safety Data Sheets - Stone

    Safety Data Sheets - Tan

    Safety Data Sheets - White

    Safety Data Sheet - White (Propack)

    Safety Data Sheets - Black