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    124 Products

    Left-Hand-Thread Steel Socket Head Screws

    Image of Product. Front orientation. Socket Head Screws. Left-Hand-Thread Steel Socket Head Screws, Fully Threaded.
    Image of Product. Front orientation. Socket Head Screws. Left-Hand-Thread Steel Socket Head Screws, Partially Threaded.
    Image of Attribute. Front orientation. Contains Annotated. Left-Hand Thread. Steel.

    Fully Threaded

    Partially Threaded

    No more righty tighty. Turn these screws to the left to tighten. They won't come loose from counterclockwise motions on reverse motors, grinders, and fans. Made of alloy steel, these are some of our strongest screws. Their deep, six-point socket keeps hex keys from slipping out and damaging the drive.
    Length is measured from under 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.
    Head
    Lg.
    Dia.
    Ht.
    Threading
    Thread
    Spacing
    Tensile Strength,
    psi
    Fastener Strength
    Grade/Class
    Specs. Met
    Each
    Black-Oxide Alloy Steel
     
    6-32
    3/8"0.226"0.138"Fully ThreadedCoarse
    170,000ASTM A57491670A146000000
    1/2"0.226"0.138"Fully ThreadedCoarse
    170,000ASTM A57491670A14800000
     
    8-32
    1/2"0.27"0.164"Fully ThreadedCoarse
    170,000ASTM A57491670A1940000
    1"0.27"0.164"Fully ThreadedCoarse
    170,000ASTM A57491670A19900000
     
    10-32
    1/2"5/16"0.19"Fully ThreadedFine
    170,000ASTM A57491670A3100000
    3/4"5/16"0.19"Fully ThreadedFine
    170,000ASTM A57491670A3130000
    1"5/16"0.19"Fully ThreadedFine
    170,000ASTM A57491670A31600000
    1 1/2"5/16"0.19"Fully ThreadedFine
    170,000ASTM A57491670A31900000
     
    1/4"-20
    1/2"3/8"1/4"Fully ThreadedCoarse
    170,000ASTM A57491670A5370000
    5/8"3/8"1/4"Fully ThreadedCoarse
    170,000ASTM A57491670A5390000
    3/4"3/8"1/4"Fully ThreadedCoarse
    170,000ASTM A57491670A54000000
    1"3/8"1/4"Fully ThreadedCoarse
    170,000ASTM A57491670A54200000
    1 1/4"3/8"1/4"Fully ThreadedCoarse
    170,000ASTM A57491670A54400000
    1 1/2"3/8"1/4"Fully ThreadedCoarse
    170,000ASTM A57491670A54600000
     
    5/16"-18
    3/4"15/32"5/16"Fully ThreadedCoarse
    170,000ASTM A57491670A58100000
    1"15/32"5/16"Fully ThreadedCoarse
    170,000ASTM A57491670A58300000
    1 1/4"15/32"5/16"Fully ThreadedCoarse
    170,000ASTM A57491670A58500000
    1 1/2"15/32"5/16"Fully ThreadedCoarse
    170,000ASTM A57491670A58700000
    2"15/32"5/16"Fully ThreadedCoarse
    170,000ASTM A57491670A58900000
     
    3/8"-16
    3/4"9/16"3/8"Fully ThreadedCoarse
    170,000ASTM A57491670A62200000
    1"9/16"3/8"Fully ThreadedCoarse
    170,000ASTM A57491670A62400000
    1 1/4"9/16"3/8"Fully ThreadedCoarse
    170,000ASTM A57491670A62600000
     
    1/2"-13
    1"3/4"1/2"Fully ThreadedCoarse
    170,000ASTM A57491670A71300000
    1 1/2"3/4"1/2"Fully ThreadedCoarse
    170,000ASTM A57491670A71600000
    2"3/4"1/2"Fully ThreadedCoarse
    170,000ASTM A57491670A72000000
     
    M4 × 0.7 mm
    6 mm7 mm4 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A00200000
    8 mm7 mm4 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A00300000
    10 mm7 mm4 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A00400000
    12 mm7 mm4 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A00500000
    16 mm7 mm4 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A00700000
    20 mm7 mm4 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A00900000
     
    M5 × 0.8 mm
    12 mm8.5 mm5 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A12500000
    16 mm8.5 mm5 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A12700000
    20 mm8.5 mm5 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A12900000
    25 mm8.5 mm5 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A1310000
     
    M6 × 1 mm
    12 mm10 mm6 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A16300000
    16 mm10 mm6 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A16400000
    20 mm10 mm6 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A16500000
    25 mm10 mm6 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A16700000
    30 mm10 mm6 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A1690000
     
    M8 × 1.25 mm
    16 mm13 mm8 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A25100000
    20 mm13 mm8 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A25200000
    25 mm13 mm8 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A25400000
    30 mm13 mm8 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A25600000
    35 mm13 mm8 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A25700000
    40 mm13 mm8 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A25800000
     
    M10 × 1.5 mm
    20 mm16 mm10 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A30200000
    25 mm16 mm10 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A30300000
    30 mm16 mm10 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A30500000
    35 mm16 mm10 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A30700000
    40 mm16 mm10 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A30900000
     
    M12 × 1.75 mm
    25 mm18 mm12 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A33600000
    30 mm18 mm12 mmFully ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A33800000
    40 mm18 mm12 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A34100000
    50 mm18 mm12 mmPartially ThreadedCoarse
    170,000Class 12.9DIN 912, ISO 476290605A34200000
     

    Left-Hand-Thread Stainless Steel Socket Head Screws

    Image of Product. Front orientation. Contains Annotated. Socket Head Screws. Left-Hand-Thread Stainless Steel Socket Head Screws.
    No more righty tighty. Turn these corrosion-resistant screws to the left to tighten. They won't come loose from counterclockwise motions on reverse motors, grinders, and fans. Their deep, six-point socket keeps hex keys from slipping out and damaging the drive.
    Length is measured from under 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 screws can.
    Head
    Lg.
    Dia.
    Ht.
    Threading
    Thread
    Spacing
    Tensile Strength,
    psi
    Each
    18-8 Stainless Steel
     
    8-32
    3/8"0.27"0.164"Fully ThreadedCoarse
    70,00092202A150000000
    1/2"0.27"0.164"Fully ThreadedCoarse
    70,00092202A15500000
    3/4"0.27"0.164"Fully ThreadedCoarse
    70,00092202A16000000
     
    10-32
    1/2"5/16"0.19"Fully ThreadedFine
    70,00092202A25500000
    3/4"5/16"0.19"Fully ThreadedFine
    70,00092202A26000000
    1"5/16"0.19"Fully ThreadedFine
    70,00092202A26500000
     
    1/4"-20
    1/2"3/8"1/4"Fully ThreadedCoarse
    70,00092202A31500000
    5/8"3/8"1/4"Fully ThreadedCoarse
    70,00092202A31700000
    3/4"3/8"1/4"Fully ThreadedCoarse
    70,00092202A31800000
    1"3/8"1/4"Fully ThreadedCoarse
    70,00092202A32100000
    1 1/4"3/8"1/4"Fully ThreadedCoarse
    70,00092202A32400000
    1 1/2"3/8"1/4"Fully ThreadedCoarse
    70,00092202A32700000
    2"3/8"1/4"Fully ThreadedCoarse
    70,00092202A33100000
     

    Left-Hand-Thread Stainless Steel Hex-Drive Flat Head Screws

    Image of Product. Front orientation. Contains MultipleImages. Flat Head Screws. Left-Hand-Thread Stainless Steel Hex-Drive Flat Head Screws.
    No more righty tighty—tighten these screws by turning them to the left. Unlike other screws, they won't come loose during counterclockwise motions on reverse motors, grinders, and fans. Made of stainless steel, they won't rust or corrode when exposed to moisture and chemicals. 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.
    Standard Profile—Standard-profile heads are the most common choice for flat head screws.
    Head
    Lg.
    Countersink
    Angle
    Flat Head
    Profile
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
     
    4-40
    1/4"82°
    Standard
    0.255"0.083"Fully Threaded70,000Material Certificate
    591512A11000000
    1/2"82°
    Standard
    0.255"0.083"Fully Threaded70,000591512A12000000
     
    6-32
    1/4"82°
    Standard
    0.307"0.097"Fully Threaded70,000591512A1300000
    1/2"82°
    Standard
    0.307"0.097"Fully Threaded70,000591512A1400000
     
    8-32
    1/2"82°
    Standard
    0.359"0.112"Fully Threaded70,000591512A15000000
    3/4"82°
    Standard
    0.359"0.112"Fully Threaded70,000591512A16000000
     
    10-32
    1/2"82°
    Standard
    0.411"0.127"Fully Threaded70,000191512A1700000
    3/4"82°
    Standard
    0.411"0.127"Fully Threaded70,000191512A1800000
     
    1/4"-20
    1/2"82°
    Standard
    0.531"0.161"Fully Threaded70,000191512A1900000
    1"82°
    Standard
    0.531"0.161"Fully Threaded70,000Material Certificate
    191512A2100000
     
    M3 × 0.5 mm
    6 mm90°
    Standard
    6.00 mm1.70 mmFully Threaded70,000Material Certificate
    591518A1100000
    10 mm90°
    Standard
    6.00 mm1.70 mmFully Threaded70,000591518A12000000
     
    M4 × 0.7 mm
    8 mm90°
    Standard
    8.00 mm2.30 mmFully Threaded70,000591518A13000000
    12 mm90°
    Standard
    8.00 mm2.30 mmFully Threaded70,000591518A14000000
     
    M5 × 0.8 mm
    10 mm90°
    Standard
    10.00 mm2.80 mmFully Threaded70,000191518A1500000
    16 mm90°
    Standard
    10.00 mm2.80 mmFully Threaded70,000191518A1600000
     
    M6 × 1 mm
    12 mm90°
    Standard
    12.00 mm3.30 mmFully Threaded70,000Material Certificate
    191518A1700000
    20 mm90°
    Standard
    12.00 mm3.30 mmFully Threaded70,000191518A1800000
     
    M8 × 1.25 mm
    16 mm90°
    Standard
    16.00 mm4.40 mmFully Threaded70,000191518A1900000
    25 mm90°
    Standard
    16.00 mm4.40 mmFully Threaded70,000Material Certificate
    191518A2100000
     

    Left-Hand-Thread Stainless Steel Button Head Hex-Drive Screws

    Image of Product. Front orientation. Contains MultipleImages. Rounded Head Screws. Left-Hand-Thread Stainless Steel Button Head Hex-Drive Screws.
    No more righty tighty. Turn these screws to the left to tighten them. Unlike other screws, they won't come loose during counterclockwise motions on reverse motors, grinders, and fans. Made of stainless steel, they won't rust or corrode when exposed to moisture and chemicals. The button head looks similar to a pan head, but it's lower and more compact, taking up less space. With six contact points, the hex drive withstands more torque than slotted and Phillips to securely grip your driver.
    Length is measured from under 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.
    Head
    Lg.
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Certificate Type
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
     
    4-40
    1/4"0.213"0.059"Fully Threaded80,000595955A22300000
    3/8"0.213"0.059"Fully Threaded80,000595955A2260000
    1/2"0.213"0.059"Fully Threaded80,000Material Certificate
    595955A2290000
    3/4"0.213"0.059"Fully Threaded80,000Material Certificate
    595955A23200000
     
    6-32
    3/8"0.262"0.073"Fully Threaded80,000595955A2450000
    1/2"0.262"0.073"Fully Threaded80,000595955A2480000
    3/4"0.262"0.073"Fully Threaded80,000595955A2510000
    1"0.262"0.073"Fully Threaded80,000595955A25400000
     
    8-32
    3/8"0.312"0.087"Fully Threaded80,000595955A2670000
    1/2"0.312"0.087"Fully Threaded80,000595955A2700000
    3/4"0.312"0.087"Fully Threaded80,000595955A27300000
    1"0.312"0.087"Fully Threaded80,000595955A27600000
     
    10-32
    3/8"0.361"0.101"Fully Threaded80,000595955A2890000
    1/2"0.361"0.101"Fully Threaded80,000595955A29200000
    3/4"0.361"0.101"Fully Threaded80,000595955A29500000
    1"0.361"0.101"Fully Threaded80,000595955A29800000
     
    1/4"-20
    3/8"0.437"0.132"Fully Threaded80,000Material Certificate
    595955A30100000
    1/2"0.437"0.132"Fully Threaded80,000595955A30400000
    3/4"0.437"0.132"Fully Threaded80,000595955A30700000
    1"0.437"0.132"Fully Threaded80,000595955A31000000
     
    M3 × 0.5 mm
    6 mm5.7 mm1.65 mmFully Threaded80,000595942A1110000
    8 mm5.7 mm1.65 mmFully Threaded80,000595942A1120000
    10 mm5.7 mm1.65 mmFully Threaded80,000595942A1130000
    12 mm5.7 mm1.65 mmFully Threaded80,000595942A11400000
     
    M4 × 0.7 mm
    8 mm7.6 mm2.2 mmFully Threaded80,000595942A1150000
    10 mm7.6 mm2.2 mmFully Threaded80,000Material Certificate
    595942A11600000
    12 mm7.6 mm2.2 mmFully Threaded80,000595942A11700000
    16 mm7.6 mm2.2 mmFully Threaded80,000595942A11800000
     
    M5 × 0.8 mm
    10 mm9.5 mm2.75 mmFully Threaded80,000595942A1190000
    12 mm9.5 mm2.75 mmFully Threaded80,000595942A12100000
    16 mm9.5 mm2.75 mmFully Threaded80,000595942A12200000
    20 mm9.5 mm2.75 mmFully Threaded80,000595942A12300000
     
    M6 × 1 mm
    10 mm10.5 mm3.3 mmFully Threaded80,000595942A12400000
    12 mm10.5 mm3.3 mmFully Threaded80,000595942A12500000
    16 mm10.5 mm3.3 mmFully Threaded80,000595942A12600000
    20 mm10.5 mm3.3 mmFully Threaded80,000595942A12700000
     
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