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    169 Products

    Stainless Steel Hex-Drive Flat Head Screws

    Image of Product. Front orientation. Flat Head Screws. Stainless Steel Hex-Drive Flat Head Screws.
    The most corrosion-resistant hex-drive flat head screws we offer. Made of stainless steel, they won't rust or corrode when exposed to moisture and chemicals, but they're not as strong as alloy steel. With six contact points, the hex drive withstands more torque than slotted and Phillips to securely grip your driver without slipping and stripping the drive.
    Length is measured from the top of the head.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these screws won't rust. However, they don't hold up to the harsh chemicals that 316 stainless steel can.
    Super-Corrosion-Resistant 316 Stainless Steel—Superior to 18-8 stainless steel, these screws won't degrade when exposed to harsh weather, salt water, and most chemicals.
    Super-Corrosion-Resistant Black-Oxide 316 Stainless Steel—Combines a finished appearance with the rust resistance of 316 stainless steel. Even if the coating wears off, these screws will hold up in just about any environment, including salt water and most chemicals.
    Standard—Standard-profile heads are the most common choice for flat head screws.
    Undercut—About a third thinner than standard heads, the undercut profile fits into shallow holes in thin material. The thin head also has more threading on the shaft, so they're often used to keep short screws from coming loose.
    Head
    Lg.
    Countersink
    Angle
    Flat Head
    Profile
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
     
    4-40
    1/8"82°
    Undercut
    0.212"0.047"Fully Threaded70,000ASME B18.3, ASTM F87910000000000000000
    3/16"82°
    Undercut
    0.255"0.047"Fully Threaded70,000ASME B18.3, ASTM F8791000000000000000
    3/16"100°
    Undercut
    0.255"0.059"Partially Threaded70,00010000000000000
    1/4"100°
    Undercut
    0.255"0.059"Partially Threaded70,00010000000000000
    5/16"100°
    Undercut
    0.255"0.059"Partially Threaded70,00010000000000000
    3/8"100°
    Undercut
    0.255"0.059"Partially Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.255"0.059"Partially Threaded70,00010000000000000
     
    6-32
    3/16"82°
    Undercut
    0.307"0.059"Fully Threaded70,000ASME B18.3250000000000000
    1/4"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
    5/16"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
    3/8"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.307"0.066"Partially Threaded70,00010000000000000
     
    8-32
    1/4"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
    5/16"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
    3/8"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.359"0.076"Partially Threaded70,00010000000000000
     
    10-24
    1/4"82°
    Undercut
    0.411"0.081"Fully Threaded70,000ASME B18.3250000000000000
    3/8"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
     
    10-32
    1/4"82°
    Undercut
    0.411"0.081"Fully Threaded70,000ASME B18.3500000000000000
    3/8"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
    1 1/2"100°
    Undercut
    0.411"0.084"Partially Threaded70,00010000000000000
     
    1/4"-20
    1/4"82°
    Undercut
    0.531"0.161"Partially Threaded70,00010000000000000
    3/8"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    7/8"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    1 1/4"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    1 1/2"100°
    Undercut
    0.531"0.105"Partially Threaded70,00010000000000000
    1 3/4"100°
    Undercut
    0.531"0.105"Partially Threaded70,000100000000000000
    2"100°
    Undercut
    0.531"0.105"Partially Threaded70,000100000000000000
     
    5/16"-18
    5/8"100°
    Undercut
    0.656"0.127"Partially Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.656"0.127"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.656"0.127"Partially Threaded70,00010000000000000
    1 1/4"100°
    Undercut
    0.656"0.127"Partially Threaded70,00010000000000000
    1 1/2"100°
    Undercut
    0.656"0.127"Partially Threaded70,00010000000000000
    1 3/4"100°
    Undercut
    0.656"0.127"Partially Threaded70,000100000000000000
    2"100°
    Undercut
    0.656"0.127"Partially Threaded70,000100000000000000
     
    3/8"-16
    3/4"100°
    Undercut
    0.781"0.157"Partially Threaded70,00010000000000000
    1"100°
    Undercut
    0.781"0.157"Partially Threaded70,00010000000000000
    1 1/4"100°
    Undercut
    0.781"0.157"Partially Threaded70,00010000000000000
    1 1/2"100°
    Undercut
    0.781"0.157"Partially Threaded70,000100000000000000
    1 3/4"100°
    Undercut
    0.781"0.157"Partially Threaded70,000100000000000000
    2"100°
    Undercut
    0.781"0.157"Partially Threaded70,000100000000000000
    2 1/2"100°
    Undercut
    0.781"0.157"Partially Threaded70,000100000000000000
    3"100°
    Undercut
    0.781"0.157"Partially Threaded70,000100000000000000
     
    1/2"-13
    1"100°
    Undercut
    0.937"0.181"Partially Threaded70,00010000000000000
    1 1/4"100°
    Undercut
    0.937"0.181"Partially Threaded70,000100000000000000
    1 1/2"100°
    Undercut
    0.937"0.181"Partially Threaded70,000100000000000000
    2"100°
    Undercut
    0.937"0.181"Partially Threaded70,000100000000000000
     
    Super-Corrosion-Resistant 316 Stainless Steel
     
    4-40
    3/16"100°
    Undercut
    0.255"0.059"Fully Threaded70,000500000000000000
    1/4"100°
    Undercut
    0.255"0.059"Fully Threaded70,000500000000000000
    5/16"100°
    Undercut
    0.255"0.059"Fully Threaded70,000500000000000000
    3/8"100°
    Undercut
    0.255"0.059"Fully Threaded70,000500000000000000
    1/2"100°
    Undercut
    0.255"0.059"Fully Threaded70,000500000000000000
     
    6-32
    1/4"100°
    Undercut
    0.307"0.066"Fully Threaded70,000500000000000000
    5/16"100°
    Undercut
    0.307"0.066"Fully Threaded70,000500000000000000
    3/8"100°
    Undercut
    0.307"0.066"Fully Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.307"0.066"Fully Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.307"0.066"Fully Threaded70,00010000000000000
     
    8-32
    3/8"100°
    Undercut
    0.359"0.076"Fully Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.359"0.076"Fully Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.359"0.076"Fully Threaded70,00010000000000000
     
    10-24
    1/4"82°
    Undercut
    0.411"0.081"Fully Threaded70,000ASME B18.3100000000000000
     
    10-32
    1/4"82°
    Undercut
    0.411"0.089"Fully Threaded70,000ASME B18.3, ASTM F879250000000000000
    3/8"100°
    Undercut
    0.411"0.084"Fully Threaded70,00010000000000000
    1/2"100°
    Undercut
    0.411"0.084"Fully Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.411"0.084"Fully Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.411"0.084"Fully Threaded70,00010000000000000
    1"100°
    Undercut
    0.411"0.084"Fully Threaded70,00010000000000000
     
    1/4"-20
    1/4"82°
    Undercut
    0.531"0.107"Fully Threaded70,000100000000000000
    1/2"100°
    Undercut
    0.531"0.105"Fully Threaded70,00010000000000000
    5/8"100°
    Undercut
    0.531"0.105"Fully Threaded70,00010000000000000
    3/4"100°
    Undercut
    0.531"0.105"Fully Threaded70,00010000000000000
    1"100°
    Undercut
    0.531"0.105"Fully Threaded70,00010000000000000
    1 1/4"100°
    Undercut
    0.531"0.105"Fully Threaded70,00010000000000000
    1 1/2"100°
    Undercut
    0.531"0.105"Fully Threaded70,00010000000000000
     
    1/4"-28
    1/4"82°
    Undercut
    0.531"0.107"Fully Threaded70,000ASME B18.3100000000000000
     
    5/16"-18
    3/4"100°
    Undercut
    0.656"0.127"Fully Threaded70,00010000000000000
    1"100°
    Undercut
    0.656"0.127"Fully Threaded70,00010000000000000
    1 1/4"100°
    Undercut
    0.656"0.127"Fully Threaded70,00010000000000000
    1 1/2"100°
    Undercut
    0.656"0.127"Fully Threaded70,00010000000000000
     
    3/8"-16
    1/2"82°
    Standard
    0.781"0.234"Fully Threaded70,000ASME B18.350000000000000
     
    M3 × 0.5 mm
    5 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000500000000000000
    6 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000500000000000000
    8 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000500000000000000
    10 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000500000000000000
    12 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000500000000000000
     
    M4 × 0.7 mm
    6 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,00010000000000000
    8 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,00010000000000000
    10 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,00010000000000000
    12 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,00010000000000000
    16 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,00010000000000000
     
    M5 × 0.8 mm
    8 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,00010000000000000
    10 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,00010000000000000
    12 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,00010000000000000
    16 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,00010000000000000
    20 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,00010000000000000
     
    M6 × 1 mm
    12 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,00010000000000000
    16 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,00010000000000000
    20 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,00010000000000000
    25 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,00010000000000000
    30 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,00010000000000000
     
    M8 × 1.25 mm
    16 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,00010000000000000
    20 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,00010000000000000
    25 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,00010000000000000
    30 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,00010000000000000
     
    M10 × 1.5 mm
    16 mm100°
    Undercut
    20 mm3.5 mmFully Threaded70,000ASTM A276100000000000000
    25 mm100°
    Undercut
    20 mm3.5 mmFully Threaded70,000ASTM A276100000000000000
    30 mm100°
    Undercut
    20 mm3.5 mmFully Threaded70,000ASTM A276100000000000000
    35 mm100°
    Undercut
    20 mm3.5 mmFully Threaded70,000ASTM A276100000000000000
    50 mm100°
    Undercut
    20 mm3.5 mmFully Threaded70,000ASTM A276100000000000000
     
    M12 × 1.75 mm
    25 mm100°
    Undercut
    24 mm4.2 mmFully Threaded70,000ASTM A276100000000000000
    30 mm100°
    Undercut
    24 mm4.2 mmFully Threaded70,000ASTM A276100000000000000
    35 mm100°
    Undercut
    24 mm4.2 mmFully Threaded70,000ASTM A276100000000000000
     
    Super-Corrosion-Resistant Black-Oxide 316 Stainless Steel
     
    M3 × 0.5 mm
    5 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000ASTM A27610000000000000
    6 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000ASTM A27610000000000000
    8 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000ASTM A27610000000000000
    10 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000ASTM A27610000000000000
    12 mm100°
    Undercut
    6 mm1.3 mmFully Threaded70,000ASTM A27610000000000000
     
    M4 × 0.7 mm
    6 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,000ASTM A27610000000000000
    8 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,000ASTM A27610000000000000
    10 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,000ASTM A27610000000000000
    12 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,000ASTM A27610000000000000
    16 mm100°
    Undercut
    8 mm1.6 mmFully Threaded70,000ASTM A27610000000000000
     
    M5 × 0.8 mm
    8 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,000ASTM A27610000000000000
    10 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,000ASTM A27610000000000000
    12 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,000ASTM A27610000000000000
    16 mm100°
    Undercut
    10 mm1.9 mmFully Threaded70,000ASTM A27610000000000000
     
    M6 × 1 mm
    12 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,000ASTM A27610000000000000
    16 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,000ASTM A27610000000000000
    20 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,000ASTM A27610000000000000
    30 mm100°
    Undercut
    12 mm2.2 mmFully Threaded70,000ASTM A27610000000000000
     
    M8 × 1.25 mm
    16 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,000ASTM A27610000000000000
    20 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,000ASTM A27610000000000000
    25 mm100°
    Undercut
    16 mm2.8 mmFully Threaded70,000ASTM A27610000000000000
     

    Steel Hex-Drive Flat Head Screws

    Image of Product. Front orientation. Flat Head Screws. Steel Hex-Drive Flat Head Screws.
    Our strongest hex-drive flat head screws. They're made of alloy steel, so they have nearly twice the tensile strength of other screws. With six contact points, the hex drive withstands more torque than slotted and Phillips to securely grip your driver without slipping and stripping the drive.
    Length is measured from the top of the head.
    Black-Oxide Alloy Steel—Typically chosen for their appearance, these screws have a dark, matte coating to create a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    Zinc-Plated Alloy Steel—A common choice for areas with occasional exposure to moisture.
    Undercut—About a third thinner than standard heads, the undercut profile fits into shallow holes in thin material. The thin head also has more threading on the shaft, so they're often used to keep short screws from coming loose.
    Head
    Lg.
    Countersink
    Angle
    Flat Head
    Profile
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Black-Oxide Alloy Steel
     
    1-64
    1/8"82°
    Undercut
    0.168"0.031"Fully Threaded130,000ASME B18.3, ASTM F83510000000000000000
     
    3-48
    3/16"82°
    Undercut
    0.187"0.042"Fully Threaded130,000ASTM F835250000000000000
     
    4-40
    1/8"82°
    Undercut
    0.255"0.047"Fully Threaded130,000ASTM F8352500000000000000
     
    5-40
    1/8"82°
    Undercut
    0.281"0.053"Fully Threaded130,000ASTM F8351000000000000000
     
    6-32
    1/8"82°
    Undercut
    0.262"0.059"Fully Threaded130,000ASTM F8351000000000000000
    5/32"82°
    Undercut
    0.262"0.059"Fully Threaded130,000ASTM F83550000000000000
    3/16"82°
    Undercut
    0.262"0.059"Fully Threaded130,000ASTM F8352500000000000000
     
    8-32
    5/32"82°
    Undercut
    0.312"0.07"Fully Threaded130,000ASTM F8351000000000000000
    3/16"82°
    Undercut
    0.359"0.07"Fully Threaded130,000ASTM F8352500000000000000
     
    10-32
    3/16"82°
    Undercut
    0.362"0.081"Fully Threaded130,000ASTM F835500000000000000
     
    1/4"-20
    1/4"82°
    Undercut
    0.531"0.107"Fully Threaded130,000ASTM F8351000000000000000
     
    1/4"-28
    1/4"82°
    Undercut
    0.477"0.107"Fully Threaded130,000ASTM F835500000000000000
     
    3/8"-16
    3/8"82°
    Undercut
    0.717"0.161"Fully Threaded130,000ASTM F835500000000000000
     
    Zinc-Plated Alloy Steel
     
    6-32
    3/16"82°
    Undercut
    0.307"0.078"Fully Threaded130,000ASTM F8352500000000000000
     
    8-32
    1/4"82°
    Undercut
    0.359"0.099"Fully Threaded130,000ASTM F83510000000000000000
     

    Tamper-Resistant Hex-Drive Stainless Steel Flat Head Screws

    Image of Product. Front orientation. Contains Annotated, MultipleImages. Flat Head Screws. Tamper-Resistant Hex-Drive Stainless Steel Flat Head Screws.
    Prevent unauthorized access and damage to components. These screws have a security pin in the drive that you can only turn with a tamper-resistant hex driver. Also known as pin-in-hex and pin-in-socket drives, the deep six-point opening helps them withstand torque without damaging the drive. Made of stainless steel, they won't rust or corrode when exposed to moisture and chemicals.
    Length is measured from the top of the head.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these screws won't rust. However, they don't hold up to the harsh chemicals that 316 stainless steel can.
    Undercut—About a third thinner than standard heads, the undercut profile fits into shallow holes in thin material. The thin head also has more threading on the shaft, so they're often used to keep short screws from coming loose.
    L-Keys—Turn screws by hand for more control and less chance of overtightening compared to power tools.
    Power Tool Bits—Pair these bits with your power tools to turn screws more quickly than manual tools.
    Screws
    L-Keys
    Power Tool Bits
    Head
    Lg.
    Countersink
    Angle
    Flat Head
    Profile
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    18-8 Stainless Steel
     
    6-32
    1/4"82°
    Undercut
    0.307"0.059"Fully Threaded70,000ASME B18.32500000000000000000000000000000000000000
     
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