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THUNDERBAY 6 Inch Diameter 36 Inch Long Double Sprial Earth Auger Bit with Sprial Drill Bit and Two Zigzag Replaceable Blades

  • Based on 129 reviews
Condition: New
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Availability: 20 left in stock
Fulfilled by THUNDERBAY PRODUCTS

Arrives Sunday, Oct 5
Order within 21 hours and 10 minutes
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Size: 6" Diameter


Style: Double Sprial


Features

  • Featuring an advanced double spiral structure, this earth auger bit ensures quicker and more efficient soil removal. Ideal for post hole digging, tree planting, or fence installation.
  • With a 6-inch wide cutting path and 36-inch long shaft, this auger bit provides the perfect size for deep and wide holes. Great for both residential and professional landscaping tasks.
  • Built from high-strength steel and finished with durable red powder coating for rust resistance and long-term use, even in tough soil conditions.
  • Comes with two zigzag replaceable blades that deliver precise cutting and extended lifespan. Easily replace when worn to maintain top drilling performance.
  • Designed to fit standard 7/8" shaft connections, compatible with most gas or electric auger powerheads. Simple to attach and ready for work in seconds.

Description

Dig smarter, not harder, with the THUNDERBAY 6-Inch Double Spiral Earth Auger Bit. Engineered for maximum efficiency, this auger bit features a double spiral design that removes soil faster and reduces workload. Whether you’re installing fence posts, planting trees, or setting up signs, this tool is built to save you time and effort. The 6-inch diameter allows for ample hole size, while the 36-inch shaft ensures deeper penetration without bending or breaking. Constructed from heavy-duty steel with a durable powder-coated finish, it’s resistant to rust and built to handle rugged terrain. Equipped with two replaceable zigzag blades, you’ll get clean, precise cuts every time. When blades wear out, simply switch them out — no need to replace the entire unit. Plus, the auger bit connects easily to most standard power heads, making it an essential addition to your toolbox. Choose THUNDERBAY for reliable, high-performance earth auger solutions that meet the demands of both professionals and DIYers.

Brand: THUNDERBAY


Tool Flute Type: Spiral


Manufacturer: THUNDERBAY


Item model number ‏ : ‎ TBZ26


Date First Available ‏ : ‎ June 10, 2025


Manufacturer ‏ : ‎ THUNDERBAY


Country of Origin ‏ : ‎ China


Best Sellers Rank: #758,831 in Tools & Home Improvement (See Top 100 in Tools & Home Improvement) #635 in Auger Drill Bits


#635 in Auger Drill Bits:


Customer Reviews: 4.5 4.5 out of 5 stars 129 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Oct 5

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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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • thunderbay auger bit
Size: 10" Diameter Style: Single Sprial
received item in a timely manner (actually 2 days prior to estimated date). have not tried it out yet, buy have the 6" and 4" auger bits and they work fine so i see no reason that this will also.
Reviewed in the United States on April 14, 2025 by snooks

  • Worked better than I expected.
Size: 10" Diameter Style: Single Sprial
The augur is light weight yet strong. I think next time I use it I may have to replace one of the bolts holding the coil in place but it sure did its job and took the excess pressure off me. The holes came out 30" deep and a nice perfect round hole. Much better than renting since the big hardware stores now require you to put your driver license scan into their database. I opted out of that as just too many places are being hacked. I can understand their position but they won't guarantee that they will not be hacked. My personal information is out there too much anyway. This worked out to be almost as cheap as renting so I am very pleased. ... show more
Reviewed in the United States on October 11, 2024 by Amazon Customer

  • Does the job.
Size: 10" Diameter Style: Single Sprial
Sharpened blade to cut roots.
Reviewed in the United States on June 3, 2021 by Kindle Customer

  • No ground is too hard for this beast!
Size: 10" Diameter Style: Single Sprial
This thing is a beast! The best value for the money hands down. Its durability and dig ability are unmatched!
Reviewed in the United States on February 11, 2025 by KENNETH H.

  • Digs a bigger hole
Size: 10" Diameter Style: Single Sprial
This works to dig a bigger hole, just what my auger extender needed.
Reviewed in the United States on July 23, 2024 by Dubbs

  • Fast delivery, great price!
Size: 10" Diameter Style: Single Sprial
Quality product! I used this attachment to help plant 30 arborvitaes.
Reviewed in the United States on September 5, 2023 by v.ant219

  • Works AWESOME!
Size: 10" Diameter Style: Single Sprial
Better than harbor fright! Drilled all my fence posts in Montana soil and ready for more!
Reviewed in the United States on November 13, 2022 by Cory R.

  • It did a great job did 6 holes for 6x6post awesome
Size: 10" Diameter Style: Single Sprial
Reviewed in the United States on June 1, 2023 by robert hall robert hall

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