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    16 Products
    About Countersinks
    industrial info icon

    Choose the right countersink angle, body diameter, and number of flutes for your application.

    Quick-Change Hex Drill-Bit Countersinks for Wood and Plastic

    Switch bits instead of tools to simplify jobs. These snap directly into drills, power screwdrivers, and other tools that accept a 1/4" hex shank. You can slide the countersink up and down the drill bit and then secure it with a set screw, so one tool will drill countersunk holes for screws of different lengths. These countersinks cut a smooth and even finish in wood and plastic on the first pass.
    High-Speed Steel
    Image of Product. Front orientation. Countersinks. For Cutting Screw Holes, Drill-Bit Countersink, For Wood, Straight Flute, Quick-Change Hex Shank, Sold Individually, 1 Countersinking End, 2 Flutes.

    2 Flutes

    The choice if you're countersinking lots of holes, these wear-resistant countersinks cut faster and last longer than carbon steel.
    Countersinks
    Replacement
    Drill Bits
    Uncoated
    Body
    Dia.
    Max. Hole
    Drilling Dp.
    For Screw
    Size
    Overall
    Lg.
    Shank
    Size
    Shank Type
    Each
    Each
    2 Flutes
     
    82° Countersink Angle
    1/2"1"No. 4
    		2 9/16"1/4"Quick-Change Hex000000000000000000000000
     

    Drill-Bit Countersinks for Wood and Plastic

    These countersinks attach at various points along the drill bit, so one tool will drill countersunk holes for screws of different lengths. They're designed to cut a smooth and even finish in wood and plastic on the first pass.
    High-Speed Steel
    Image of Product. Front orientation. Countersinks. Drill-Bit Countersink, 1 Countersinking End, For Wood, For Cutting Screw Holes, Sold Individually, Straight Flute, 4 Flutes.

    4 Flutes

    The choice if you're countersinking lots of holes, these wear-resistant countersinks cut faster and last longer than carbon steel.
    Countersinks
    Counterbore Collars
    Uncoated
    Body
    Dia.
    For Drill
    Bit Size
    For Screw
    Size
    Overall
    Lg.
    Each
    OD
    Wd.
    Each
    4 Flutes
     
    82° Countersink Angle
    5/16"7/64"No. 4
    		3/4"00000000000009/16"1/4"000000000000
     
    90° Countersink Angle
    5/16"7/64"No. 4
    		3/4"0000000000009/16"1/4"00000000000
     
    Carbon Steel
    Image of Product. Front orientation. Countersinks. Drill-Bit Countersink, 1 Countersinking End, For Wood, For Cutting Screw Holes, Sold Individually, Straight Flute, 4 Flutes.

    4 Flutes

    Stronger than high-speed steel, so it will cut through harder materials. However, high-speed steel is more precise, lasts longer, and cuts at higher speeds.
    Countersinks
    Counterbore Collars
    Uncoated
    Body
    Dia.
    For Drill
    Bit Size
    For Screw
    Size
    Overall
    Lg.
    Each
    OD
    Wd.
    Each
    4 Flutes
     
    82° Countersink Angle
    5/16"7/64"No. 4
    		7/8"00000000000009/16"1/4"000000000000
     

    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
     

    Built-In-Pilot Counterbores

    The pilot centers the counterbore and prevents wobbling for an accurate cut on the first try. With dimensions that match standard screw-head diameters and thread diameters, this is your plug-and-play option for pilot-driven counterbores.
    High-Speed Steel
    Image of Product. Front orientation. ZoomedIn view. Counterbores. Built-In-Pilot Counterbores.
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Titanium Nitride (TiN) Coated—Withstand heat, corrosion, and abrasion for longer than uncoated counterbores, so the cutting edges stay sharper.
    Pilot
    Shank
    Uncoated
    Titanium Nitride
    (TiN) Coated
    For Screw
    Size
    Body
    Dia.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Each
    Each
    No. 4
    		0.186"0.112"0.156"3 7/8"5/32"Round4000000000000000000000000000
     

    Counterbores for High-Profile Rounded-Head Screws

    Image of Product. Front orientation. Counterbores. Counterbores for High-Profile Rounded-Head Screws.
    Cut flat, close-fitting recesses for fillister-head screws. These counterbores cut deeply enough for screws with tall head profiles to sit flush with the surface.
    High-Speed Steel
    Durable and wear resistant, these counterbores make accurate cuts in most materials without chipping or cracking.
    Uncoated
    For Screw
    Size
    Body
    Dia.
    Overall
    Lg.
    Shank
    Type
    No. of
    Flutes
    Pilot
    Lg.
    Each
    No. 4
    		0.198"2 5/8"Round20.170"0000000000000
     

    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.
    Titanium Nitride (TiN) Coated—Withstand heat, corrosion, and abrasion for longer than uncoated counterbores, so the cutting edges stay sharper.
    Pilot
    Shank
    Uncoated
    Titanium Nitride
    (TiN) Coated
    For Screw
    Size
    Body
    Dia.
    Dia.
    Lg.
    Overall
    Lg.
    Dia.
    Type
    No. of
    Flutes
    Each
    Each
     
    1/64" Oversize
    No. 4
    		0.206"0.128"0.156"3 7/8"5/32"Round4000000000000000000000000000
     
    1/32" Oversize
    No. 4
    		0.221"0.143"0.156"3 7/8"5/32"Round40000000000000000000000000
     

    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
     
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