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    169 Products

    Duct Flanges

    Mount flanges to air handlers and HVAC equipment to start a run of duct. They also create a secure joint between sections of duct—attach a flange to each piece. Also known as angle rings.
    With Mounting Holes—Ready to install, these flanges secure with screws.
    Without Mounting Holes—Drill your own holes or weld into place.
    Steel—Strong for a long life, these steel flanges can be painted or coated. Unless it’s finished, steel is best for dry environments.
    Galvanized Steel—Corrosion resistant and affordable, galvanized steel is the most commonly used ductwork material.
    Corrosion-Resistant 304 Stainless Steel—The most corrosion-resistant metal duct we sell. It won’t rust or degrade in systems that exhaust chemical fumes or vent heat from industrial ovens and dryers.
    Lightweight Aluminum—One-third the weight of steel, aluminum ductwork is easier to handle during installation. Like galvanized steel, it resists rust in wet environments but won’t last as long.
    PVC—Withstand chemicals that would eat away at most metal duct. It’s often used in systems that exhaust corrosive gases, vapors, and fumes.
    Flange
    Mounting
    Duct
    Size
    ID
    Overall
    Dp.
    Ht.
    Thk.
    Fasteners
    Included
    No. of
    Holes
    Hole Dia.
    Each
    With Mounting Holes
    Image of Product. Side1 orientation. Contains Annotated. Duct Flanges, With Mounting Holes.
    Image of Product. Front orientation. Duct and Fittings. Duct Flanges, With Mounting Holes.
     
    Steel
    33 1/16"1"1"1/8"No69/32"000000000000
    3 1/23 9/16"1"1"9/64"No69/32"000000000000
    44 1/16"1"1"1/8"No69/32"000000000000
    4 1/24 9/16"1"1"9/64"No69/32"000000000000
    55 1/16"1"1"1/8"No69/32"000000000000
    5 1/25 9/16"1"1"9/64"No69/32"000000000000
    66 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    77 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    88 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    99 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1010 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1111 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1212 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1313 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1414 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1515 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1616 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    1717 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    1818 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    1919 1/8"1 1/2"1 1/2"3/16"No127/16"0000000000000
    2020 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2121 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2222 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2323 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2424 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2525 1/8"1 1/2"1 1/2"3/16"No167/16"000000000000
    2626 1/8"2"2"3/16"No167/16"000000000000
    2727 1/8"2"2"3/16"No167/16"000000000000
    2828 1/8"2"2"3/16"No167/16"000000000000
    2929 1/8"2"2"3/16"No167/16"000000000000
    3030 1/8"2"2"3/16"No167/16"000000000000
    3232 1/8"2"2"3/16"No167/16"000000000000
    3434 1/8"2"2"3/16"No167/16"000000000000
    3636 1/8"2"2"3/16"No167/16"0000000000000
    3838 1/8"2"2"3/16"No247/16"0000000000000
    4040 1/8"2"2"3/16"No247/16"00000000000000
    4242 1/8"2"2"3/16"No247/16"00000000000000
    4444 1/8"2"2"3/16"No247/16"00000000000000
    4646 1/8"2"2"3/16"No247/16"00000000000000
    4848 1/8"2"2"3/16"No247/16"00000000000000
    5252 1/8"2"2"3/16"No247/16"00000000000000
     
    Galvanized Steel
    33 1/16"1"1"1/8"No69/32"000000000000
    3 1/23 17/32"1"1"9/64"No69/32"0000000000000
    44 1/16"1"1"1/8"No69/32"000000000000
    4 1/24 17/32"1"1"9/64"No69/32"0000000000000
    55 1/16"1"1"1/8"No69/32"000000000000
    5 1/25 17/32"1"1"9/64"No69/32"0000000000000
    66 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    77 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    88 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    99 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1010 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1111 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1212 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1313 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1414 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1515 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1616 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    1717 3/16"1 1/2"1 1/2"3/16"No87/16"000000000000
    1818 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    2020 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2121 3/16"1 1/2"1 1/2"3/16"No127/16"000000000000
    2222 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2323 3/16"1 1/2"1 1/2"3/16"No127/16"000000000000
    2424 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2626 1/8"2"2"3/16"No167/16"0000000000000
    2828 1/8"2"2"3/16"No167/16"0000000000000
    3030 1/8"2"2"3/16"No167/16"0000000000000
    3434 3/16"2"2"3/16"No167/16"0000000000000
    3636 3/16"2"2"3/16"No167/16"0000000000000
    3838 3/16"2"2"3/16"No247/16"0000000000000
    4040 3/16"2"2"3/16"No247/16"0000000000000
     
    Corrosion-Resistant 304 Stainless Steel
    33 1/16"7/8"1"1/8"No69/32"000000000000
    3 1/23 9/16"1"1"9/64"No69/32"0000000000000
    44 1/16"1"1"1/8"No69/32"000000000000
    4 1/24 9/16"1"1"9/64"No69/32"0000000000000
    55 1/16"1"1"1/8"No69/32"000000000000
    5 1/25 9/16"1"1"9/64"No69/32"0000000000000
    66 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    77 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    88 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    99 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1010 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1111 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1212 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1313 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1414 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1515 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1616 1/8"1 1/2"1 1/2"3/16"No87/16"0000000000000
    1818 1/8"1 1/2"1 1/2"3/16"No87/16"0000000000000
    1919 1/8"1 1/2"1 1/2"3/16"No127/16"00000000000000
    2020 1/8"1 1/2"1 1/2"3/16"No127/16"0000000000000
    2222 1/8"1 1/2"1 1/2"3/16"No127/16"0000000000000
    2424 1/8"1 1/2"1 1/2"3/16"No127/16"0000000000000
    2626 1/8"2"2"3/16"No167/16"0000000000000
    2828 1/8"2"2"3/16"No167/16"0000000000000
    3030 1/8"2"2"3/16"No167/16"0000000000000
    3232 1/8"2"2"3/16"No167/16"00000000000000
    3636 1/8"2"2"3/16"No167/16"00000000000000
    3838 1/8"2"2"3/16"No247/16"00000000000000
    4040 1/8"2"2"3/16"No247/16"00000000000000
     
    Lightweight Aluminum
    33 1/16"1"1"7/64"No69/32"000000000000
    3 1/23 9/16"1"1"7/64"No69/32"000000000000
    44 1/16"1"1"7/64"No69/32"000000000000
    4 1/24 9/16"1"1"7/64"No69/32"000000000000
    55 1/16"1"1"7/64"No69/32"000000000000
    5 1/25 9/16"1"1"7/64"No69/32"000000000000
    66 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    77 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    88 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    99 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1010 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1111 1/8"1 1/4"1 1/4"1/8"No63/8"000000000000
    1212 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1313 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1414 1/8"1 1/2"1 1/2"1/8"No87/16"000000000000
    1616 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    1818 1/8"1 1/2"1 1/2"3/16"No87/16"000000000000
    2020 1/8"1 1/2"1 1/2"3/16"No127/16"000000000000
    2424 1/8"1 1/2"1 1/2"3/16"No127/16"0000000000000
    2626 1/8"2"2"3/16"No167/16"0000000000000
     
    PVC
    44 1/2"2 1/4"1 7/8"1/4"No45/16"00000000000
    66 5/8"3 1/4"1 1/2"1/4"No85/16"000000000000
    88 5/8"3 1/4"1 1/2"1/4"No105/16"000000000000
    1010 3/4"3 1/4"1 3/8"1/4"No125/16"0000000000000
    1212 3/4"3 1/2"1 3/8"1/4"No165/16"0000000000000
    1414"3 1/2"1 3/4"1/4"No165/16"0000000000000
    1616"3 1/2"1 3/4"1/4"No185/16"0000000000000
     
    Without Mounting Holes
    Image of Product. Front orientation. Duct and Fittings. Duct Flanges, Without Mounting Holes.
    Image of Product. Side1 orientation. Contains Annotated. Duct Flanges, Without Mounting Holes.
     
    Steel
    33 1/16"1"1"1/8"00000000000
    44 1/16"1"1"1/8"000000000000
    55 1/16"1"1"1/8"000000000000
    66 1/8"1 1/4"1 1/4"1/8"000000000000
    77 1/8"1 1/4"1 1/4"1/8"000000000000
    88 1/8"1 1/4"1 1/4"1/8"000000000000
    99 1/8"1 1/4"1 1/4"1/8"000000000000
    1010 1/8"1 1/4"1 1/4"1/8"000000000000
    1111 1/8"1 1/4"1 1/4"1/8"000000000000
    1212 1/8"1 1/2"1 1/2"1/8"000000000000
    1313 1/8"1 1/2"1 1/2"1/8"000000000000
    1414 1/8"1 1/2"1 1/2"1/8"000000000000
    1515 1/8"1 1/2"1 1/2"1/8"000000000000
    1616 1/8"1 1/2"1 1/2"3/16"000000000000
    1818 1/8"1 1/2"1 1/2"3/16"000000000000
    2020 1/8"1 1/2"1 1/2"3/16"000000000000
    2222 1/8"1 1/2"1 1/2"3/16"000000000000
    2424 1/8"1 1/2"1 1/2"3/16"000000000000
    2626 1/8"2"2"3/16"000000000000
    2828 1/8"2"2"3/16"000000000000
    3030 1/8"2"2"3/16"000000000000
     
    Corrosion-Resistant 304 Stainless Steel
    44 1/16"1"1"1/8"000000000000
    55 1/16"1"1"1/8"000000000000
    66 1/8"1 1/4"1 1/4"1/8"000000000000
    77 1/8"1 1/4"1 1/4"1/8"000000000000
    88 1/8"1 1/4"1 1/4"1/8"000000000000
    99 1/8"1 1/4"1 1/4"1/8"000000000000
    1010 1/8"1 1/4"1 1/4"1/8"000000000000
    1111 1/8"1 1/4"1 1/4"1/8"000000000000
    1212 1/8"1 1/2"1 1/2"1/8"000000000000
    1313 1/8"1 1/2"1 1/2"1/8"000000000000
    1414 1/8"1 1/2"1 1/2"1/8"000000000000
    1515 1/8"1 1/2"1 1/2"1/8"000000000000
    1616 1/8"1 1/2"1 1/2"3/16"0000000000000
    1818 1/8"1 1/2"1 1/2"3/16"0000000000000
    2020 1/8"1 1/2"1 1/2"3/16"0000000000000
    2222 1/8"1 1/2"1 1/2"3/16"0000000000000
    2424 1/8"1 1/2"1 1/2"3/16"0000000000000
    2626 1/8"2"2"3/16"0000000000000
    2828 1/8"2"2"3/16"0000000000000
    3030 1/8"2"2"3/16"0000000000000
     
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