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    MasterSeal NP 125: One-component, elastomeric, gun-grade thermoplastic sealant and adhesive

    Formerly: Sonolastic Clear 25

    How does MasterSeal NP 125 work?

    MasterSeal NP 125 is a one-component, high-performance, non-priming, gun-grade, thermoplastic adhesive and sealant. It requires no mixing and bonds tenaciously to common building materials, including concrete and clay roof tiles, metal flashings and masonry.

    Recommended uses:

    • Residential
    • Commercial
    • Sheet roofing
    • Liquid applied roofs
    • Metal roofs
    • Shingled and tiled roofs
    • Between adjacent layers of roof tile
    • Sealing edge and ridge tiles
    • Penetration seals
    • Flashings
    • Skylight frames
    • Termination bars and reglets
    • Parapet expansion joints
    • Lap seals in metal roof assemblies
    • Sealing wood forms

    What are the unique features of MasterSeal NP 125?

    • Superior holding power for longer lasting seals
    • Suitable for exterior applications (roofing)
    • Bonds similar and dissimilar materials
    • Clear formula blends with any substrate color
    • Wide temperature application range makes MasterSeal NP 125 suitable for all climates

    What are the benefits of MasterSeal NP 125?

    • One-component formula requires no mixing, helping to reduce labor costs
    • Joint movement capability of 25% total provides excellent flexibility, keeping moving joints tightly sealed
    • Easy to gun and tool, speeding up application and making neater joints
    • Weather resistant for long-lasting weather tight seals
    • Compatible with non-rigid paints and can be painted

    US / Canada Product Information

    Data Guide

    Data Guide (French)

    Certification Letter

    LEED Letter

    Color Reference - MasterSeal NP 125

    Direct contact

    Master Builders Solutions Technical Support

    Construction Systems


    Safety Data Sheet (SDS)

    Find all available safety data sheets for this product.



    Product Certifications

    Generate a free certificate of conformance for a specific BASF construction product.

    Related Literature

    Certification Letter

    pdf (55.25 Kb)

    Color Reference

    pdf (166.60 Kb)

    Data Guide

    pdf (105.27 Kb)

    Data Guide (French)

    pdf (137.88 Kb)

    Joint Sealants Brochure - Spanish

    pdf (749.31 Kb)

    LEED Letter

    pdf (71.66 Kb)

    MasterSeal NP 1 NOCAL OFF WHT SDS

    pdf (344.05 Kb)

    MasterSeal NP 1 NOCAL OFF WHT SDS

    pdf (349.38 Kb)

    MasterSeal NP 1 NOCAL OFF WHT SDS

    pdf (330.95 Kb)

    MasterSeal NP 1 NOCAL OFF WHT SDS

    pdf (332.20 Kb)

    Sealant Performance Selection Guide

    pdf (872.11 Kb)