McMaster-Carr logo
    Filter by
    Container Type
    Seal Class
    Minimum Temperature
    Reaches Full Strength
    DFARS Specialty Metals
    Tensile Strength
    Industrial Info Snippet
    Begins to Harden
    Paintable
    Flammability Rating
    Industrial Info Compare
    Elongation
    U.S.–Mexico–Canada Agreement (USMCA) Qualifying
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Primer Required for Use On
    Forward
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Print
    How can we improve?
    Comments
    E-mail address (if you would like a response)
    16 Products
    About Sealants
    industrial info icon

    Select a sealant that can stretch, contract, and expand enough for your joints.

    Metal Duct HVAC Sealants

    Image of Product. Front orientation. Sealants. Metal Duct HVAC Sealants, Cartridge.
    Image of Product. Front orientation. Sealants. Metal Duct HVAC Sealants, Pail.

    Cartridge

    Pail

    Seal metal-to-metal joints in ductwork. These sealants are non-sagging, so they won't drip from vertical and overhead surfaces.
    Container
    Temp.,
    ° F
    Size
    Type
    Begins to
    Harden, min.
    Reaches Full
    Strength, hr.
    Elongation
    Joint Compression/Expansion
    Tolerance
    Tensile
    Strength
    Hardness Rating
    Min.
    Max.
    For
    Joining
    Color
    (Clarity)
    Each
    Acrylic Plastic
    10.1 fl. oz.Cartridge1548Not RatedNot RatedNot RatedSoft (Durometer 20A)-40200MetalGray (Opaque)73335A6500000
    1 gal.Pail1548Not RatedNot RatedNot RatedSoft (Durometer 20A)-40200MetalGray (Opaque)73335A6600000
     

    HVAC Sealants

    Form flexible water-resistant seals on metal, plastic, and rubber joints in heating, ventilation, air conditioning, and refrigeration applications. These sealants are non-sagging, so they won't drip from vertical and overhead surfaces. Made from silicone rubber, sealants are RTV (room-temperature vulcanizing).
    Elongation and joint compression/expansion tolerance indicate flexibility—the higher the values are, the more joint movement sealants can sustain.
    Dow Silicone Rubber
    Image of Product. Front orientation. Sealants. HVAC Sealants.
    Container
    Size, fl.
    oz.
    Type
    Begins to
    Harden, min.
    Reaches Full
    Strength, hr.
    Elongation
    Joint Compression/Expansion
    Tolerance
    Tensile Strength,
    psi
    Hardness Rating
    Temp. Range,
    ° F
    Certification
    Food Industry Std.
    Flammability
    Rating
    For Joining
    Choose a Color (Clarity)
    Each
    10.3Cartridge524600%-25% to 25%325Soft (Durometer 27A)-40 to 350UL Listed
    		FDA Compliant 21 CFR 177.2600
    		UL 94 HB
    		Composite
    Metal
    Plastic
    Rubber
    Metal to Composite
    Metal to Plastic
    Metal to Rubber    		Aluminum, Clear, White (Semi-Clear)1919N3000000
    Sealant Primers
    Each
    PR-1200 Primer for Dow 700, 732, 733, 734, 736, 737, 739, 786, 995, Loctite®, 76435T21, 76435T11, 7545A611 and 1919N3 Sealants (10.9 fl. oz. Bottle)7442A23000000
    Silicone Rubber
    Image of Product. Front orientation. Sealants. HVAC Sealants.
    Container
    Size, fl.
    oz.
    Type
    Begins to
    Harden, min.
    Reaches Full
    Strength, hr.
    Elongation
    Joint Compression/Expansion
    Tolerance
    Tensile
    Strength
    Hardness Rating
    Temp. Range,
    ° F
    Mil. Spec.
    For Joining
    Choose a Color (Clarity)
    Each
    9.4Cartridge2024Not Rated-25% to 25%Not RatedSoft (Durometer 26A)-60 to 400Fed. Spec. TT-S-00230
    Fed. Spec. TT-S-001543 Class A    		Composite
    Metal
    Plastic
    Rubber
    Metal to Composite
    Metal to Plastic
    Metal to Rubber    		Clear (Clear), Gray (Opaque), White (Opaque)1919N1600000

    Expansion Plugs for Conduit

    Image of Product. Bottom orientation. Expansion Plugs. Expansion Plugs for Conduit.
    Seal conduit openings to keep water, dirt, and animals from damaging your wiring. When you twist the nut on top of these plugs, a rubber seal expands to close off the end of your conduit. Tie a rope or pull line to the loop at either end of these plugs to hold them in place during installation.
    For
    Conduit
    Material
    Trade
    Size
    ID
    Overall
    Ht.
    Seal
    Loop
    Features
    Each
    Loop Nut—Plastic Plate
    3/4
    		0.77" to 1.02"3 3/8"Synthetic RubberPlasticInternal Eyebolt6564N1100000
    1
    		0.99" to 1.39"3 3/4"Synthetic RubberPlasticInternal Eyebolt6564N120000
    1 1/4
    		1.16" to 1.51"3 13/16"Synthetic RubberPlasticInternal Eyebolt6564N130000
    1 1/2
    		1.46" to 1.83"4"Synthetic RubberPlasticInternal Eyebolt6564N140000
    2
    		1.83" to 2.39"4"Synthetic RubberPlasticInternal Eyebolt6564N150000
    2 1/2
    		2.4" to 2.99"7 1/2"Synthetic RubberPlasticInternal Eyebolt6564N1600000
    3
    		2.92" to 3.45"7 5/8"Synthetic RubberPlasticInternal Eyebolt6564N1700000
    3 1/23.41" to 3.9"6 3/4"Synthetic RubberPlasticInternal Eyebolt6564N1800000
    4
    		3.94" to 4.33"7 1/2"Synthetic RubberPlasticInternal Eyebolt6564N1900000
    54.85" to 5.25"7 5/8"Synthetic RubberPlasticInternal Eyebolt6564N2100000
    65.92" to 6.37"6 3/4"Synthetic RubberPlasticInternal Eyebolt6564N2200000
     
    back to top