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toolant Four Spiral Flute Cobalt Step Drill Bit(Pro), 3/16" - 1-3/8"(19 Step Size) Unibit Step Drill Bit, 3/8" Tri-Falt Shank Step Bit for Metal, Stainless Steel, Aluminum, Plastic

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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, May 6
Order within 13 hours and 57 minutes
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Size: 3/16" - 1-3/8"


Features

  • FOUR SPIRAL FLUTE - Four cutting blades design guarantees a faster and smoother cutting. Feels like a hot knife through butter!
  • TiAlN COATING - With 89HRC surface hardness, harder materials can be cut and higher cutting speeds can be achieved.
  • M35 COBALT HSS STEP DRILL - Prefect for 1/8"(3mm) thick Stainless Steel/Metal Sheet/Wood/Plastic/Aluminum Sheet/Copper and other metal sheets.
  • DIMENSION - Includes from 7/8" to 1-3/8". Popular Size 7/8", 1-1/8", 1-3/8" labeled.
  • WARRANTY - If you are not fully satisfied for any reason, please contact us for 100% refund or replacement.

Features

  • FOUR SPIRAL FLUTE - Four cutting blades design guarantees a faster and smoother cutting. Feels like a hot knife through butter!
  • TiAlN COATING- With 89HRC surface hardness, harder materials can be cut and higher cutting speeds can be achieved.
  • M35 COBALT HSS STEP DRILL - Prefect for Stainless Steel/Metal Sheet/Wood/Plastic/Aluminum Sheet/Copper and other metal sheets.
  • 3/8" SHANK - Eliminate slipping
  • DIMENSION - Includes from 7/8" to 1-3/8". Popular Size 7/8, 1-1/8", 1-3/8" labeled

Package Dimensions ‏ : ‎ 3.62 x 1.69 x 1.65 inches; 8.15 Ounces


Item model number ‏ : ‎ AU0580004


Date First Available ‏ : ‎ February 17, 2022


Manufacturer ‏ : ‎ AugTouf


Country of Origin ‏ : ‎ China


Best Sellers Rank: #1,350 in Industrial & Scientific (See Top 100 in Industrial & Scientific) #2 in Step Drill Bits


#2 in Step Drill Bits:


Customer Reviews: 4.5 4.5 out of 5 stars 1,008 ratings


Material: Cobalt Steel


Cutting Diameter: 1-3/8 Inches


Finish Type: Titanium Aluminum Nitride


Shank Type: 3-Flat


Cutting Angle String: 135 Degrees


Cutting Diameter: 1-3/8 Inches


Item Dimensions: 3.14 x 1.49 x 1.49 inches


Minimum Bore Diameter: 0.19 Inches


Material Type: Cobalt Steel


Finish Types: Titanium Aluminum Nitride


Shank Type: 3-Flat


Surface Recommendation: Aluminum,Stainless Steel,Wood,Copper,Plastic,Metal,Steel


Cutting Angle String: 135 Degrees


Tool Flute Type: Four Spiral Flute


Point Style: Diamond Point


Number of Flutes: 4


Brand Name: AugTouf


Model: AU0580004


Manufacturer: AugTouf


Included Components: 19 step 1-3/8" Four Flute Cobalt Step Drill Bit(1pc)


Unit Count: 1.0 Count


Warranty Description: 90 days warranty - free replacement or refund


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, May 6

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Absolutely best bits I own
Size: 1/8" - 7/8" (3pcs Set)
These relatively inexpensive bits outperform very high dollar carbide machinist bits, and other much more expensive cobalt bits. The cut so fast that the material barely has any chance to get hot which makes them last forever. I've been using them not for several months and I am very sincerely impressed. It's really hard to trust sellers these days. I think I paid 60 bucks to try them in my body shop just as a chance they might work on the lighter sheet metal and they performed so well and lasted so long I have started using them in my machine shop. They are suitable for cutting harder than mild steel, alloys and stainless with no issue whatsoever. I cannot speak highly enough of how surprised and utterly impressed I am with the performance. The most surprising part is the cost! They are the cheapest bits I own and they are also the best drill bits I own! I'm putting together a list to start replacing my professional machinist quality drill bits with these as they go bad and dull. They cost less than sharpening my bits and I have yet to dull any of these as of yet. Very surprised, impressed, and happy with them! I wish more things were like this. I'm happy I took a chance and bought these taking a low risk chance that had really taught me a wonderful lesson. ... show more
Reviewed in the United States on September 12, 2024 by Chisty Rich

  • Great unibit
Size: 1/4" - 3/4"
Hardy and cuts any hole with minimal effort
Reviewed in the United States on April 2, 2026 by ed griffith

  • Great tool, worth every penny.
Size: 1/8" - 1/2"
Used it for the first time yesterday. Works well, worth every penny. Drilled 3 half inch holes in 3/16 mild steel, in half tided time it took the day before with 3 standard titanium coated HSS bits. And this bit still looks new.
Reviewed in the United States on January 22, 2026 by Bill R.

  • Pretty good with a caveat
Size: 1/8" - 7/8" (3pcs Set)
Purchased 3 years ago, the unibits I have owned. Aggressive and maintain sharpness except for the pilot tip that dulls quickly. I work around this by predrilling a small hole with a regular drill bit first. Note I recently broke one where the shaft gave up on a non-impact drill A 1/2" shaft would be better, makes me wonder how these are "impact rated". I will be replacing the broken one with the same brand. ... show more
Reviewed in the United States on March 1, 2026 by Gern

  • They are flawless
Size: 1/8" - 7/8" (3pcs Set)
Best stepper i have bought in a long time. Sent the 1/4 bit through a solid cast cummins block. No problems.
Reviewed in the United States on February 19, 2026 by jarren jones

  • Toughest unibit I've ever used, update 8 months later
Size: 1/8" - 1/2"
I am in the automotive electronics industry. I have used different types and brands of step bits for the last 20 years. Most of them turn to garbage after drilling through semi thick metal once or twice. And it ruins the tip. I have only used this new one on types of plastic and twice on sheet metal in the body of a vehicle. So far this bit works better than any I have ever used. It is so sharp you must be careful using it on plastic because it will cut a hole bigger than you want very quickly if you're not careful. I hope I have success in keeping it sharp using it on metal. Here's update on review. I have now used this bit drilling through multiple metal panels on automobiles. I have not had one issue with this product darling or causing me any problems. I don't know how it will do drilling through 8 inch solid steel but through body panels and floor panels on cars it does exceptionally well. . Here's an update from the middle of July 2023. This bit is really rugged. It will drill through 8 inch to quarter inch solid steel on a truck steak bed. I drilled the pilot hole with an 8 inch bit and used it to make the hole up to a 3/8. This bit is extremely Sharp and extremely brittle. I advise spraying silicone on it and keep your drill moving slowly watching it peel the metal. When you're going to that slow speed with this bit it works wonders. It's amazing. But I usually use it for thin metal in vehicles and it has no problem whatsoever. It gets seven Stars as far as I'm concerned. But be careful it is brutal when you are drilling big holes it can hang up and snap. ... show more
Reviewed in the United States on December 23, 2022 by J. Trenthem

  • Definitely not impact rated.
Size: 1/4" - 1-1/8"
I have been in the trades for 30 years. I decided to give this a try because of cost. I was on my 35th hole of just drilling through tin and it snapped. The cutting is absolutely great but it’s definitely not impact rated considering it was a Dewalt impact. lol
Reviewed in the United States on March 17, 2026 by Amazon Customer

  • Sharp
Size: 3/16" - 7/8"
Works excellent
Reviewed in the United States on March 22, 2026 by Robert W.

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