Extensions for Round-Shank Drill Bits
One Piece
Two Piece
Attach to the shank of a drill bit to extend its reach.
To attach one-piece extensions, insert a drill bit into the extension and tighten the knurled collar.
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 technical drawings and 3-D models, click on a part number.
For Drill Bit | ||||||||
|---|---|---|---|---|---|---|---|---|
| Size | Size Decimal Equivalent | Shank Size | Shank Size | Overall Lg. | OD | Material | Each | |
Inch | ||||||||
One Piece | ||||||||
| 1/64" | 0.0156" | 1/64" | 1/8" | 4" | 1/8" | Steel | 00000000 | 000000 |
| 1/64" | 0.0156" | 1/64" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 1/32" | 0.0313" | 1/32" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 1/32" | 0.0313" | 1/32" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 3/64" | 0.0469" | 3/64" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 1/16" | 0.0625" | 1/16" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
Two Piece | ||||||||
| 1/16" | 0.0625" | 1/16" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 1/16" | 0.0625" | 1/16" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 5/64" | 0.0781" | 5/64" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 5/64" | 0.0781" | 5/64" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 3/32" | 0.0938" | 3/32" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 3/32" | 0.0938" | 3/32" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 7/64" | 0.1094" | 7/64" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 7/64" | 0.1094" | 7/64" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 1/8" | 0.1250" | 1/8" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 1/8" | 0.1250" | 1/8" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 9/64" | 0.1406" | 9/64" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 9/64" | 0.1406" | 9/64" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 5/32" | 0.1563" | 5/32" | 1/4" | 4 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 5/32" | 0.1563" | 5/32" | 1/4" | 9 1/2" | 5/16" | Steel | 00000000 | 00000 |
| 11/64" | 0.1719" | 11/64" | 1/4" | 4 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 11/64" | 0.1719" | 11/64" | 1/4" | 9 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 3/16" | 0.1875" | 3/16" | 1/4" | 4 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 3/16" | 0.1875" | 3/16" | 1/4" | 9 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 13/64" | 0.2031" | 13/64" | 1/4" | 4 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 13/64" | 0.2031" | 13/64" | 1/4" | 9 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 7/32" | 0.2188" | 7/32" | 1/4" | 4 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 7/32" | 0.2188" | 7/32" | 1/4" | 9 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 15/64" | 0.2344" | 15/64" | 1/4" | 4 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 15/64" | 0.2344" | 15/64" | 1/4" | 9 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 1/4" | 0.2500" | 1/4" | 1/4" | 4 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 1/4" | 0.2500" | 1/4" | 1/4" | 9 1/2" | 7/16" | Steel | 00000000 | 00000 |
| 1/4" | 0.2500" | 1/4" | 3/8" | 4 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 1/4" | 0.2500" | 1/4" | 3/8" | 9 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 17/64" | 0.2656" | 17/64" | 3/8" | 4 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 17/64" | 0.2656" | 17/64" | 3/8" | 9 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 9/32" | 0.2813" | 9/32" | 3/8" | 4 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 9/32" | 0.2813" | 9/32" | 3/8" | 9 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 19/64" | 0.2969" | 19/64" | 3/8" | 4 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 19/64" | 0.2969" | 19/64" | 3/8" | 9 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 5/16" | 0.3125" | 5/16" | 3/8" | 4 1/2" | 9/16" | Steel | 00000000 | 00000 |
| 5/16" | 0.3125" | 5/16" | 3/8" | 9 1/2" | 9/16" | Steel | 00000000 | 00000 |
Wire Gauge | ||||||||
One Piece | ||||||||
| 80 ga | 0.0135" | 0.014" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 80 ga | 0.0135" | 0.014" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 79 ga | 0.0145" | 0.015" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 79 ga | 0.0145" | 0.015" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 78 ga | 0.0160" | 0.016" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 78 ga | 0.0160" | 0.016" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 77 ga | 0.0180" | 0.018" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 77 ga | 0.0180" | 0.018" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 76 ga | 0.0200" | 0.02" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 76 ga | 0.0200" | 0.02" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 75 ga | 0.0210" | 0.021" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 75 ga | 0.0210" | 0.021" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 74 ga | 0.0225" | 0.023" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 74 ga | 0.0225" | 0.023" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 73 ga | 0.0240" | 0.024" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 73 ga | 0.0240" | 0.024" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 72 ga | 0.0250" | 0.025" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 72 ga | 0.0250" | 0.025" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 71 ga | 0.0260" | 0.026" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 71 ga | 0.0260" | 0.026" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 70 ga | 0.0280" | 0.028" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 70 ga | 0.0280" | 0.028" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 69 ga | 0.0292" | 0.029" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 69 ga | 0.0292" | 0.029" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 68 ga | 0.0310" | 0.031" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 68 ga | 0.0310" | 0.031" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 67 ga | 0.0320" | 0.032" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 67 ga | 0.0320" | 0.032" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 66 ga | 0.0330" | 0.033" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 66 ga | 0.0330" | 0.033" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 65 ga | 0.0350" | 0.035" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 65 ga | 0.0350" | 0.035" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 64 ga | 0.0360" | 0.036" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 64 ga | 0.0360" | 0.036" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 63 ga | 0.0370" | 0.037" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 63 ga | 0.0370" | 0.037" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 62 ga | 0.0380" | 0.038" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 62 ga | 0.0380" | 0.038" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 61 ga | 0.0390" | 0.039" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |
| 61 ga | 0.0390" | 0.039" | 3/16" | 4" | 3/16" | Steel | 00000000 | 00000 |
| 60 ga | 0.0400" | 0.04" | 1/8" | 4" | 1/8" | Steel | 00000000 | 00000 |