Make it Snappy Tools SD-3 Flat Bottom Counterbores

Q: What is a flat-bottom counterbore used for?

It creates a flat-bottomed recessed hole so fasteners like lag screws, lag bolts, washer-head screws, and T-nuts seat properly. See our drill bits & drivers .

Q: What sizes are available?

Five sizes: 1/8" x 3/8", 3/16" x 1/2", 1/4" x 3/4", 5/16" x 1", and 3/8" x 1" . You can also buy the 5-Pc. set with a canvas pouch.

Q: What is the drill bit made of?

The drills are high speed steel coated with Titanium Nitride (TiN) to increase wear resistance and extend life.

Q: What shank do these counterbores have?

Each has a 1/4" hex Power Bit shank that works with Snappy's Quick Change chuck.

Q: Does it drill the pilot hole too?

Yes. The 3-flute counterbore creates the pilot hole and the flat-bottomed counterbore in one step .

Q: How do I adjust the counterbore depth?

An oversized set screw makes adjusting the counterbore quick and easy, so you can set the drill depth without fumbling.

Q: Can I buy these as a set?

Yes. They're offered individually in five sizes, or as a 5-Pc. set with a canvas pouch . Browse more drilling & boring tools .

Q: Who makes the SD-3 counterbores?

They are made by Make it Snappy Tools . Pair them with our Forstner bits for more boring options.

Description Reviews Q&A

Snappy Counterbores for a One-Step Hole

Countersink bits are great when you're using wood screws with a cone-shaped head. However, if you're using lag screws, lag bolts, washer head screws, T-nuts & more, you need a countersunk hole with a flat bottom to properly seat the screw. That's where the Snappy SD-3 Counterbores are the perfect tool. The 3-flute counterbore creates a pilot hole and counterbores a flat bottomed hole in one step.

The drill bits are high speed steel and coated with Titanium Nitride (TiN) to increase wear resistance. Each counterbore has a 1/4" hex Power Bit shank to work with Snappy's Quick Change chuck.

Another great feature for woodworkers is the oversized set screw for the counterbore. Rather than fumbling around trying to tighten or loosen the screw, this oversized screw makes adjusting the counterbore a simple task. Sometimes it's the little things that make a big difference.

The counterbores are offered in five sizes, or buy the 5-Pc. set with canvas pouch and save!

Sizes Include:

1/8" x 3/8"
3/16" x 1/2"
1/4" x 3/4"
5/16" x 1"
3/8" x 1"

Frequently Asked Questions

What is a flat-bottom counterbore used for?

It creates a flat-bottomed recessed hole so fasteners like lag screws, lag bolts, washer-head screws, and T-nuts seat properly. See our drill bits & drivers.

How is this different from a countersink?

A countersink makes a cone-shaped recess for cone-headed wood screws, while the SD-3 makes a flat-bottomed hole for flat-bottomed fasteners. It also drills the pilot hole in the same step.

What sizes are available?

Five sizes: 1/8" x 3/8", 3/16" x 1/2", 1/4" x 3/4", 5/16" x 1", and 3/8" x 1". You can also buy the 5-Pc. set with a canvas pouch.

What is the drill bit made of?

The drills are high speed steel coated with Titanium Nitride (TiN) to increase wear resistance and extend life.

What shank do these counterbores have?

Each has a 1/4" hex Power Bit shank that works with Snappy's Quick Change chuck.

Does it drill the pilot hole too?

Yes. The 3-flute counterbore creates the pilot hole and the flat-bottomed counterbore in one step.

How do I adjust the counterbore depth?

An oversized set screw makes adjusting the counterbore quick and easy, so you can set the drill depth without fumbling.

Can I buy these as a set?

Yes. They're offered individually in five sizes, or as a 5-Pc. set with a canvas pouch. Browse more drilling & boring tools.

What fasteners need a flat-bottomed hole?

Lag screws, lag bolts, washer-head screws, T-nuts, and similar flat-bottomed hardware seat best in a flat-bottomed counterbore.

Who makes the SD-3 counterbores?

They are made by Make it Snappy Tools. Pair them with our Forstner bits for more boring options.

Make it Snappy Tools SD-3 Flat Bottom Counterbores