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    9 Products
    About Counterbores
    industrial info icon

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

    Built-In-Pilot Counterbore Sets

    Image of Product. Front orientation. Counterbores. Built-In-Pilot Counterbore Sets.
    Create flat, close-fitting recesses for a range of screw-head sizes. The pilot centers and stabilizes the counterbore for an accurate cut and even surface on the first try.
    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
    Each
    Uncoated High-Speed Steel
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"10Round400000000000000
     

    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
    Shank
    Type
    No. of
    Flutes
    Each
    Uncoated High-Speed Steel
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"101/64"Round400000000000000
    No. 4, No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"101/32"Round40000000000000
    M3, M4, M5, M6, M8, M10, M12, M1480.5 mmRound40000000000000
     

    Changeable-Pilot Counterbores Sets

    Image of Product. Front orientation. Counterbores. Changeable-Pilot Counterbores Sets.
    A handful of counterbores and changeable pilots give you the versatility of dozens of normal counterbores. For each hole, mix and match counterbores and pilots to correspond with your screw-head and screw-shank diameter.
    High-Speed Steel—Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Body Dia.
    No. of
    Pieces
    Shank
    Type
    Includes
    Container
    Type
    Each
    Uncoated High-Speed Steel
    1/4", 5/16", 3/8", 7/16", 1/2"5Round10 PilotsWood Case00000000000000
     

    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
    Each
    Uncoated High-Speed Steel
    No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"9Round2Plastic Case000000000000000
    No. 5, No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2"9Round2Plastic Case00000000000000
    M3, M4, M5, M6, M8, M10, M12, M14, M169Round2Plastic Case00000000000000
     

    Drill-Bit Counterbore Sets for Wood

    Image of Product. Front orientation. Counterbores. Drill-Bit Counterbore Sets for Wood.
    Drill and counterbore holes of different depths without changing tools. These counterbores move along the drill bit (sold separately) and lock into place with set screws to match the length of the screw you're installing.
    Body Dia.
    No. of
    Pieces
    Container
    Type
    Each
    Uncoated Steel
    3/46", 1/4", 5/16", 3/8", 7/16", 1/2"6Wood Stand00000000000000
     
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