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    MasterFlow 640

    Grout accelerator for MasterFlow 648

    Formerly: MasterFlow 648 CP Grout Accelerator

    How does MasterFlow 640 work?

    When MasterFlow 640 is added to MasterFlow 648, it accelerates the cure rate at low temperatures. MasterFlow 640 should be used in temperatures below 60º F (16º C).

    Recommended uses:

    • Where heating exterior spaces is impractical
    • Where temperatures fall below 60º F (16º C)
    • Where high early strengths are required

    What are the unique features of MasterFlow 640?

    • Accelerated cure rate
    • Early strength development

    What are the benefits of MasterFlow 640?

    • Enables cold-weather applications
    • Early return to service
    Product Information

    Data Guide

    Certification Letter

    LEED Letter 

    Safety Data Sheet