IRWIN Unibit #4 Step Drill Bit (10231) Review
Irwin Tools IRWIN Step Drill Bit, 1/8-Inch to 1/2-Inch Step, 1/4-Inch Shank (10231) Silver|Silver metallic
$19.65 (price as of 2026-11-07)
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Reddit score
2.7 Based on 2 Reddit owner comments · Top 100% of 3 tracked step drill bits
| Owner sentiment | 2.4 | |
| Recommendations | 1.0 | |
| Spec score | Not rated | |
| Value | 4.7 |
How these are computed: methodology. Components without evidence show “Not rated” and their weight moves to the others.
Limited Reddit owner feedback. We need more owner experiences before this score is reliable, so this page is not yet in our sitemap.
Is the IRWIN Unibit #4 Step Drill Bit (10231) worth it?
Based on 2 Reddit owner comments, the IRWIN Unibit #4 Step Drill Bit (10231) scores 2.7 out of 5 (owner comments average 2.0 stars), and the theme owners raise most is durability (1 mention).
Who it suits
- Not observed: owners have not yet praised a specific theme often enough.
Who should skip it
- Durability matters a lot to you (1 critical owner mention)
What Reddit owners say
0 positive and 2 critical owner comments. Quotes link to the original Reddit comment.
Key specs
As listed on the Amazon product page we checked; missing fields are never estimated.
- Save time because you don't need to change drills for different-sized round holes in thin materials. Each drill acts as a pilot for the next size.
- Patented single-flute cutting edge gives greater control through steps and a true round hole every time.
- Ideal for drilling holes into thin materials such as stainless steel, copper, brass, aluminum, plastic and laminates.
- SpeedPoint tip penetrates faster than previous Unibits and prevents walking. 3-faltted hex shank prevents slipping in drill chuck.
- Drill diameters etched in flute for easy identification.
| Brand Name | IRWIN |
|---|---|
| Model | 10231 |
| UPC | 787721839125 780541552908 038548101019 |
| Set Name | 1/8" to 1/2" 13 SZ |
| Unit Count | 1 Count |
| Global Trade Identification Number | 00038548101019 |
| Number of Packs | 1 |
| Part Number | 10231 |
| Number of Pieces | 1 |
| Included Components | STEP DRILL #1 1/8-1/2" 13 SZ |
| Item Type Name | STEP DRILL #1 1/8-1/2" 13 SZ |
| Item Weight | 1.44 ounces |
| Warranty Description | Limited lifetime |
| Cutting Diameter | 12.7 millimeters |
| Item Dimensions | 6 x 2.87 x 0.75 inches |
| Material Type | Stainless Steel |
| Finish Types | Black Oxide |
| Shank Type | Hex 3-flat |
| Surface Recommendation | Aluminum,Brass,Copper,Metal,Plastic,Stainless Steel,Steel |
| Cutting Angle String | 118 degrees |
| Tool Flute Type | Spiral |
| Point Style | Step Point |
| Number of Flutes | 1 |
Drills Supply is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. Commissions never affect scores, rankings, or verdicts.
FAQ
Is the IRWIN Unibit #4 Step Drill Bit (10231) worth it?
Based on 2 Reddit owner comments, the IRWIN Unibit #4 Step Drill Bit (10231) scores 2.7 out of 5 (owner comments average 2.0 stars), and the theme owners raise most is durability (1 mention).
What do Reddit owners complain about with the IRWIN Unibit #4 Step Drill Bit (10231)?
The most common critical theme is durability (1 mentions).
How much does the IRWIN Unibit #4 Step Drill Bit (10231) cost?
It was $19.65 on Amazon when we checked on 2026-11-07. Prices change, so check Amazon for the current price.
Alternatives
3.1 (1 owner comments)
$27.99 (price as of 2026-11-07)
“Came back next day with a Milwaukee step bit set, ate it up in seconds!”
Read review →Keep deciding
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Last updated 2026-11-07. Amazon listing ASIN B00004THYX.