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    21 Products
    About Counterbores
    industrial info icon

    Create flat-bottomed holes, so your screw heads sit flush, recessed, or slightly raised.

    Pilot Type

    Counterbore Type

    Size Designation

    Sold As

    Oversized Counterbores

    Designed to give screw heads a slightly loose fit, these counterbores are a bit wider than standard sizes. The extra clearance prevents binding and leaves room for a seal or O-ring around the screw head.
    High-Speed Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Oversized Counterbores.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Pilot
    Shank
    Uncoated
    For Screw
    Size
    Body Dia.,
    mm
    Dia.,
    mm
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Mfr.
    Each
     
    0.5 mm Oversize
    M3
    		6.03.50.219"4 1/2"3/16"Round4Alvord-Polk Tool2740A11000000
    M4
    		7.54.50.250"5"1/4"Round4Alvord-Polk Tool2740A1200000
    M5
    		9.05.50.281"5 5/8"5/16"Round4Alvord-Polk Tool2740A1300000
    M6
    		10.56.50.313"5 5/8"5/16"Round4Alvord-Polk Tool2740A1400000
    M8
    		13.58.50.375"6 1/2"1/2"Round4Alvord-Polk Tool2740A1500000
    M10
    		16.510.50.500"7"1/2"Round4Alvord-Polk Tool2740A1600000
    M12
    		18.512.50.500"7 1/8"1/2"Round4Alvord-Polk Tool2740A1700000
    M14
    		21.514.50.563"7 1/2"5/8"Round4Alvord-Polk Tool2740A18000000
    M16
    		24.516.50.625"7 5/8"5/8"Round4Alvord-Polk Tool2740A22000000
    M20
    		30.520.50.750"8 1/8"7/8"Round4Alvord-Polk Tool2740A26000000
     

    Drill-Point Counterbore Sets

    Image of Product. Front orientation. Counterbores. Drill-Point Counterbore Sets.
    Skip a step when installing screws of various thread diameters in metal. With a sharp point on the tip, these counterbores drill a pilot hole topped with a flat recess for the screw head. That's faster and more accurate than switching to a counterbore in between passes with your drill bit.
    High-Speed Steel—Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    For Screw Size
    No. of
    Pieces
    Shank
    Type
    No. of
    Flutes
    Container
    Type
    Mfr.
    Each
    Uncoated High-Speed Steel
    M3, M4, M5, M6, M8, M10, M12, M14, M16
    		9Round2Plastic CaseLink Industries9940N1130000000
     

    Oversized Counterbore Sets

    Image of Product. Front orientation. Counterbores. Oversized Counterbore Sets.
    Designed to give screw heads a slightly loose fit, these counterbores are a bit wider than standard sizes. The extra clearance prevents binding and leaves room for a seal or O-ring around the screw head.
    High-Speed Steel—Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    For Screw Size
    No. of
    Pieces
    Oversize
    Amount, mm
    Shank
    Type
    No. of
    Flutes
    Mfr.
    Each
    Uncoated High-Speed Steel
    M3, M4, M5, M6, M8, M10, M12, M14
    		80.5Round4Alvord-Polk Tool2740A190000000
     

    Drill-Point Counterbores

    Skip a step when installing screws in metal. With a sharp point on the tip, these counterbores drill a pilot hole topped with a flat recess for the screw head. That's faster and more accurate than switching to a counterbore in between passes with your drill bit.
    High-Speed Steel
    Image of Product. Front orientation. Counterbores. Drill-Point Counterbores.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Shank
    Uncoated
    For Screw
    Size
    Body Dia.,
    mm
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Max. Hole Drilling
    Dp., mm
    Mfr.
    Each
    M3
    		5.91 1/4"1/4"Round26.35Link Industries29445A21000000
    M4
    		7.51 3/8"1/4"Round27.54Link Industries29445A2200000
    M5
    		9.11 1/2"5/16"Round27.94Link Industries29445A2300000
    M6
    		10.71 9/16"5/16"Round29.52Link Industries29445A2400000
    M8
    		13.41 13/16"7/16"Round211.11Link Industries29445A2500000
    M10
    		16.62 1/16"1/2"Round214.29Link Industries29445A2600000
    M12
    		18.72 7/16"5/8"Round215.87Link Industries29445A2700000
    M14
    		21.82 5/8"5/8"Round216.67Link Industries29445A2800000
    M16
    		24.62 3/4"5/8"Round217.46Link Industries29445A2900000
     
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