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    107 Products

    Extensions for Round-Shank Drill Bits

    Attach to the shank of a drill bit to extend its reach.
    One-Piece Extensions—To attach one-piece extensions, insert a drill bit into the extension and tighten the knurled collar.
    Two-Piece Extensions—To attach two-piece extensions, insert a drill bit into the collet, then thread the collet onto the extension and tighten with a wrench.
    For Drill Bit
    Size
    Size Decimal
    Equiv.
    Shank
    Size
    Shank
    Size
    Overall
    Lg.
    OD
    Material
    Each
    For Inch Drill Bits
     
    Image of Product. Front orientation. Drill Bit Extensions. Extensions for Round-Shank Drill Bits, One-Piece Extensions.
    One-Piece Extensions
    1/64"0.0156"1/64"1/8"4"1/8"Steel00000000000000
    1/64"0.0156"1/64"3/16"4"3/16"Steel0000000000000
    1/32"0.0313"1/32"1/8"4"1/8"Steel0000000000000
    1/32"0.0313"1/32"3/16"4"3/16"Steel0000000000000
    3/64"0.0469"3/64"3/16"4"3/16"Steel0000000000000
    1/16"0.0625"1/16"3/16"4"3/16"Steel0000000000000
     
    Image of Product. Front orientation. Contains Annotated. Drill Bit Extensions. Extensions for Round-Shank Drill Bits, Two-Piece Extensions.
    Two-Piece Extensions
    1/16"0.0625"1/16"1/4"4 1/2"5/16"Steel0000000000000
    1/16"0.0625"1/16"1/4"9 1/2"5/16"Steel0000000000000
    5/64"0.0781"5/64"1/4"4 1/2"5/16"Steel0000000000000
    5/64"0.0781"5/64"1/4"9 1/2"5/16"Steel0000000000000
    3/32"0.0938"3/32"1/4"4 1/2"5/16"Steel0000000000000
    3/32"0.0938"3/32"1/4"9 1/2"5/16"Steel0000000000000
    7/64"0.1094"7/64"1/4"4 1/2"5/16"Steel0000000000000
    7/64"0.1094"7/64"1/4"9 1/2"5/16"Steel0000000000000
    1/8"0.1250"1/8"1/4"4 1/2"5/16"Steel0000000000000
    1/8"0.1250"1/8"1/4"9 1/2"5/16"Steel0000000000000
    9/64"0.1406"9/64"1/4"4 1/2"5/16"Steel0000000000000
    9/64"0.1406"9/64"1/4"9 1/2"5/16"Steel0000000000000
    5/32"0.1563"5/32"1/4"4 1/2"5/16"Steel0000000000000
    5/32"0.1563"5/32"1/4"9 1/2"5/16"Steel0000000000000
    11/64"0.1719"11/64"1/4"4 1/2"7/16"Steel0000000000000
    11/64"0.1719"11/64"1/4"9 1/2"7/16"Steel0000000000000
    3/16"0.1875"3/16"1/4"4 1/2"7/16"Steel0000000000000
    3/16"0.1875"3/16"1/4"9 1/2"7/16"Steel0000000000000
    13/64"0.2031"13/64"1/4"4 1/2"7/16"Steel0000000000000
    13/64"0.2031"13/64"1/4"9 1/2"7/16"Steel0000000000000
    7/32"0.2188"7/32"1/4"4 1/2"7/16"Steel0000000000000
    7/32"0.2188"7/32"1/4"9 1/2"7/16"Steel0000000000000
    15/64"0.2344"15/64"1/4"4 1/2"7/16"Steel0000000000000
    15/64"0.2344"15/64"1/4"9 1/2"7/16"Steel0000000000000
    1/4"0.2500"1/4"1/4"4 1/2"7/16"Steel0000000000000
    1/4"0.2500"1/4"1/4"9 1/2"7/16"Steel0000000000000
    1/4"0.2500"1/4"3/8"4 1/2"9/16"Steel0000000000000
    1/4"0.2500"1/4"3/8"9 1/2"9/16"Steel0000000000000
    17/64"0.2656"17/64"3/8"4 1/2"9/16"Steel0000000000000
    17/64"0.2656"17/64"3/8"9 1/2"9/16"Steel0000000000000
    9/32"0.2813"9/32"3/8"4 1/2"9/16"Steel0000000000000
    9/32"0.2813"9/32"3/8"9 1/2"9/16"Steel0000000000000
    19/64"0.2969"19/64"3/8"4 1/2"9/16"Steel0000000000000
    19/64"0.2969"19/64"3/8"9 1/2"9/16"Steel0000000000000
    5/16"0.3125"5/16"3/8"4 1/2"9/16"Steel0000000000000
    5/16"0.3125"5/16"3/8"9 1/2"9/16"Steel0000000000000
     
    For Wire Gauge Drill Bits
     
    Image of Product. Front orientation. Drill Bit Extensions. Extensions for Round-Shank Drill Bits, One-Piece Extensions.
    One-Piece Extensions
    800.0135"0.014"1/8"4"1/8"Steel0000000000000
    800.0135"0.014"3/16"4"3/16"Steel0000000000000
    790.0145"0.015"1/8"4"1/8"Steel0000000000000
    790.0145"0.015"3/16"4"3/16"Steel0000000000000
    780.0160"0.016"1/8"4"1/8"Steel0000000000000
    780.0160"0.016"3/16"4"3/16"Steel0000000000000
    770.0180"0.018"1/8"4"1/8"Steel0000000000000
    770.0180"0.018"3/16"4"3/16"Steel0000000000000
    760.0200"0.02"1/8"4"1/8"Steel0000000000000
    760.0200"0.02"3/16"4"3/16"Steel0000000000000
    750.0210"0.021"1/8"4"1/8"Steel0000000000000
    750.0210"0.021"3/16"4"3/16"Steel0000000000000
    740.0225"0.023"1/8"4"1/8"Steel0000000000000
    740.0225"0.023"3/16"4"3/16"Steel0000000000000
    730.0240"0.024"1/8"4"1/8"Steel0000000000000
    730.0240"0.024"3/16"4"3/16"Steel0000000000000
    720.0250"0.025"1/8"4"1/8"Steel0000000000000
    720.0250"0.025"3/16"4"3/16"Steel0000000000000
    710.0260"0.026"1/8"4"1/8"Steel0000000000000
    710.0260"0.026"3/16"4"3/16"Steel0000000000000
    700.0280"0.028"1/8"4"1/8"Steel0000000000000
    700.0280"0.028"3/16"4"3/16"Steel0000000000000
    690.0292"0.029"1/8"4"1/8"Steel0000000000000
    690.0292"0.029"3/16"4"3/16"Steel0000000000000
    680.0310"0.031"1/8"4"1/8"Steel0000000000000
    680.0310"0.031"3/16"4"3/16"Steel0000000000000
    670.0320"0.032"1/8"4"1/8"Steel0000000000000
    670.0320"0.032"3/16"4"3/16"Steel0000000000000
    660.0330"0.033"1/8"4"1/8"Steel0000000000000
    660.0330"0.033"3/16"4"3/16"Steel0000000000000
    650.0350"0.035"1/8"4"1/8"Steel0000000000000
    650.0350"0.035"3/16"4"3/16"Steel0000000000000
    640.0360"0.036"1/8"4"1/8"Steel0000000000000
    640.0360"0.036"3/16"4"3/16"Steel0000000000000
    630.0370"0.037"1/8"4"1/8"Steel0000000000000
    630.0370"0.037"3/16"4"3/16"Steel0000000000000
    620.0380"0.038"1/8"4"1/8"Steel0000000000000
    620.0380"0.038"3/16"4"3/16"Steel0000000000000
    610.0390"0.039"1/8"4"1/8"Steel0000000000000
    610.0390"0.039"3/16"4"3/16"Steel0000000000000
    600.0400"0.04"1/8"4"1/8"Steel0000000000000
    600.0400"0.04"3/16"4"3/16"Steel0000000000000
    590.0410"0.041"1/8"4"1/8"Steel0000000000000
    590.0410"0.041"3/16"4"3/16"Steel0000000000000
    580.0420"0.042"1/8"4"1/8"Steel0000000000000
    580.0420"0.042"3/16"4"3/16"Steel0000000000000
    570.0430"0.043"1/8"4"1/8"Steel0000000000000
    570.0430"0.043"3/16"4"3/16"Steel0000000000000
    560.0465"0.047"1/8"4"1/8"Steel0000000000000
    560.0465"0.047"3/16"4"3/16"Steel0000000000000
    550.0520"0.052"3/16"4"3/16"Steel0000000000000
    540.0550"0.055"3/16"4"3/16"Steel0000000000000
    530.0595"0.06"3/16"4"3/16"Steel0000000000000
     
    Image of Product. Front orientation. Contains Annotated. Drill Bit Extensions. Extensions for Round-Shank Drill Bits, Two-Piece Extensions.
    Two-Piece Extensions
    430.0890"0.089"1/4"4 1/2"5/16"Steel0000000000000
    430.0890"0.089"1/4"9 1/2"5/16"Steel0000000000000
    400.0980"0.098"1/4"4 1/2"5/16"Steel0000000000000
    400.0980"0.098"1/4"9 1/2"5/16"Steel0000000000000
    300.1285"0.129"1/4"4 1/2"5/16"Steel0000000000000
    300.1285"0.129"1/4"9 1/2"5/16"Steel0000000000000
    210.1590"0.159"1/4"4 1/2"5/16"Steel0000000000000
    210.1590"0.159"1/4"9 1/2"5/16"Steel0000000000000
    110.1910"0.191"1/4"4 1/2"7/16"Steel0000000000000
    110.1910"0.191"1/4"9 1/2"7/16"Steel0000000000000
    100.1935"0.194"1/4"4 1/2"7/16"Steel0000000000000
    100.1935"0.194"1/4"9 1/2"7/16"Steel0000000000000
     
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