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    31 Products

    Tamper-Resistant Tri-Groove-Drive Steel Round Head Screws

    Image of Product. Front orientation. Rounded Head Screws. Tamper-Resistant Tri-Groove-Drive Steel Round Head Screws.
    Good luck trying to force off these screws. The tri-groove drive has a sloped shape with three notches that makes it nearly impossible to grip without a tri-groove driver. They're often found on electrical boxes, machine control panels, and critical equipment where unauthorized access is a concern.
    Length is measured from under the head.
    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    Power Tool Bits—Pair these bits with your power tools to turn screws more quickly than manual tools.
    Screws
    Power Tool Bits
    Head
    Lg.
    Dia.
    Ht.
    Threading
    Tensile Strength,
    psi
    Pkg.
    Qty.
    Pkg.
    Each
    Zinc-Plated Steel
     
    6-32
    3/8"0.26"0.12"Fully Threaded80,000500000000000000000000000000000
    1/2"0.26"0.12"Fully Threaded80,0005000000000000000000000000000
    3/4"0.26"0.12"Fully Threaded80,0005000000000000000000000000000
     
    8-32
    3/8"0.28"0.148"Fully Threaded80,0005000000000000000000000000000
    1/2"0.28"0.148"Fully Threaded80,0005000000000000000000000000000
    3/4"0.28"0.148"Fully Threaded80,0005000000000000000000000000000
    1"0.28"0.148"Fully Threaded80,0005000000000000000000000000000
    1 1/4"0.28"0.148"Fully Threaded80,0005000000000000000000000000000
    1 1/2"0.28"0.148"Fully Threaded80,0005000000000000000000000000000
     
    10-24
    1/2"0.375"0.15"Fully Threaded80,0005000000000000000000000000000
    3/4"0.375"0.15"Fully Threaded80,0005000000000000000000000000000
    1"0.375"0.15"Fully Threaded80,000250000000000000000000000000
    1 1/2"0.375"0.15"Fully Threaded80,000250000000000000000000000000
     
    10-32
    1/2"0.375"0.15"Fully Threaded80,0005000000000000000000000000000
    3/4"0.375"0.15"Fully Threaded80,0005000000000000000000000000000
    1"0.375"0.15"Fully Threaded80,0005000000000000000000000000000
    1 1/2"0.375"0.15"Fully Threaded80,000250000000000000000000000000
     
    1/4"-20
    1/2"0.375"0.155"Fully Threaded80,0005000000000000000000000000000
    3/4"0.375"0.155"Fully Threaded80,0005000000000000000000000000000
    1"0.375"0.155"Fully Threaded80,000250000000000000000000000000
    1 1/2"0.375"0.155"Fully Threaded80,000250000000000000000000000000
    2"0.375"0.155"Fully Threaded80,0002500000000000000000000000000
    2 1/2"0.375"0.155"Partially Threaded80,000100000000000000000000000000
     
    5/16"-18
    5/8"0.57"0.275"Fully Threaded80,0002500000000000000000000000000
    3/4"0.57"0.275"Fully Threaded80,0002500000000000000000000000000
    1"0.57"0.275"Fully Threaded80,0002500000000000000000000000000
     

    Tri-Groove Bits

    Image of Product. Front orientation. Screwdriver Bits. Tri-Groove Bits.
    Turn tri-groove screws with these bits. They're commonly used to fasten signs, lighting fixtures, and other types of public property.
    Quick-Change Hex Shank—Lock these bits directly into power tools. They won't wobble as much as bits paired with an adapter, so they are the best choice for high-precision tasks.
    Steel—Best for dry environments, since moisture will cause these bits to rust.
    Overall
    For Screw Size
    Lg.
    Dia.
    Material
    Each
    For Power Tools
     
    1/4" Quick-Change Hex Shank Size
    No. 1, No. 2, No. 3, No. 4
    1 3/8"3/8"Steel0000000000000
    No. 5, No. 6, No. 7, No. 8, No. 9, No. 10, No. 11
    1 1/4"1/2"Steel000000000000
    No. 8, No. 9, No. 10, No. 11, No. 12, 1/4"
    1 1/4"7/8"Steel000000000000
    No. 12, 5/16"
    1 1/4"3/4"Steel000000000000
     

    Tri-Groove Bit Sets

    Image of Product. Front orientation. Screwdriver Bits. Tri-Groove Bit Sets.
    The bits in these sets turn tri-groove screws. They're commonly used to fasten signs, lighting fixtures, and other types of public property.
    Quick-Change Hex Shank—Lock these bits directly into power tools. They won't wobble as much as bits paired with an adapter, so they are the best choice for high-precision tasks.
    High-Speed Steel—Harder and more heat resistant than plain steel. These bits withstand the intense friction of high-speed power tools without deforming or softening.
    Components
    Included
    Bits Included
    Material
    Container
    Type
    Each
    For Power Tools
     
    1/4" Quick-Change Hex Shank Size
    4 BitsTri-Groove: 0.375" O'all Dia. for No. 1-No. 8 (1 3/8" O'all Lg.)
    Tri-Groove: 0.5" O'all Dia. for No. 5-No. 11 (1 1/4" O'all Lg.)
    Tri-Groove: 0.75" O'all Dia. for No. 12-No. 13, 5/16" (1 1/4" O'all Lg.)
    Tri-Groove: 0.875" O'all Dia. for No. 8-No. 12, 1/4" (1 1/4" O'all Lg.)
    High-Speed SteelPlastic Pouch0000000000000
     
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