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Internet # 203570983

Model # HDGQA

3/8 in. AutoStart Carbide Hole Saw Quick Change Mandrel

  • Carbide tip provides extended life in porcelain and granite
  • Walk-free cuts without pilot holes, for 3/4" to 4-1/8" hole saws
  • Starts holes accurately; use with AN01 or AN02 adapter
  • View More Details
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Return this item within 90 days of purchase. Read Return Policy
Product Details

About This Product

The Bosch Auto Start pilot bit is one of the latest additions to the Bosch hole saw product line. As with Bosch's entire line of hole saws, these products are part of the patented Quick Change Universal Hole Saw system, which lets you change hole saws in seconds. This pilot bit features a spring loaded, retractable shaft that allows walk-free cutting without a pilot hole. Also this bit features a unique grind that starts holes accurately every time.


  • Carbide tip provides extended life in porcelain and granite
  • For use with diamond hole saws (3/4 in. - 4-1/8 in.)
  • Use with Bosch mandrel models PCM38, PCM12 and PCMSDSPL
  • Extend the life of your quick change mandrel
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  • Return Policy

Product Information

Internet # 203570983

Model # HDGQA

Additional Resources

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Bit Diameter

1 in

Bit Length (in.)


Drilling Depth (in)


Hole Saw Diameter (in)


Shank Diameter

3/8 in


Arbor included


Arbor Size


Bit Material


Drill Bit Type

Hole Saw

Drill Bit Type(s) Included

Hole Saw



Material Cut

Tile (wet or dry)

Min Chuck Size Required

3/8 In.

Pilot Bit Included




Shank Style


Teeth Per Inch


Tools Product Type

Power Tool

Questions & Answers

Q:I have the hole saw (HDG4) and looking for the missing piece. ill this allow me to get this hole saw going?
by|Jun 14, 2023
1 Answer
Answer This Question

A:  This HDGQA is a pilot bit use for hole saw like your HDG4. For further assistance, contact us at 1-877-BOSCH99 (1-877-267-2499) from Mon-Fri 7A-7P CST.

by|Jun 23, 2023
    Q:Will this work with the Milwaukee drill
    by|Aug 23, 2022
    3 Answers
    Answer This Question

    A:  It's for Bosch hole saws.

    by|Aug 24, 2022

      A:  Yes, must line up flat on drill post to flat spines on drill. An excellent drill bit.

      by|Aug 25, 2022

        A:  Hi there! This HDGQA Mandrel has 3/8 shank which will work to holesaws. Also, for the drill, any standrad drill driver will work as long as it accepts the shank size. For further assistance, contact us at 1-877-BOSCH99 (1-877-267-2499) from Mon-Fri 7A-7P CST.

        by|Aug 26, 2022
          Q:Is there an adapter for this? Or do you have buy holesaws that have the adapter built in?
          by|Aug 26, 2020
          2 Answers
          Answer This Question

          A:  I can attach the mandrel to the drill. Its the bit I purchased the Bosch daredevil 4 1/8" bit and it does not have the clip to connect it to the mandrel. It appears that you have to purchase bits designed for this mandrel specifically, which does not work for me as I have several holesaws to begin with, just purchased this to make a hole in cinderblock. I guess I will need to exchange this.

          by|Aug 29, 2020

            A:  The Mandrel which is HDGQA model doesn't need an adapter. It can be attached to a 3 jaw chuck drill/driver, while the hole saw is connected to it for drilling process. For further assistance, contact us at 1-877-267-2499 from Mon-Fri 7A-7P CST.

            by|Aug 27, 2020
              Q:I just purchased this Bosch auto start mandrel,Why does the tip turn freely in the mandrel, how will it drill
              by|May 26, 2017
              2 Answers
              Answer This Question

              A:  The tip is not a drill but rather a stabilizer for the hole saw. Chipping out a nick in the tile to hold the mandrel tip before drilling with the hole saw worked well for me; I'm otherwise a complete novice at home repairs.

              by|Apr 7, 2020

              A:  Thank you for your question. This HDGQA auto start tip isn't a drill bit. This is used as a guide on tiles to ensure that the diamond saw stays in place. For further assistance, contact us at 1-877-BOSCH99 (1-877-267-2499) from M-F 7a-7p CST.

              by|May 4, 2023
                Showing 1-4 of 4

                Customer Reviews

                4.5 out of 5

                • 4.5 out of 39 reviews
                • 100% recommend this product
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                Showing 1-10 of 39 reviews
                Must have item for Bosch hole saws.
                • Verified Purchase
                Great idea, too bad it broke during its first use. It could still be used in its broken condition, but the pieces no longer stayed together.
                Response from BoschToolsMar 12, 2024
                Hi! Thank you for your review of the HDGQA. We do apologize that it broke after the first use. Home Depot offers a 30-day return policy, and we encourage you to take advantage of it. If you would like to provide us with additional information, please email us at bosch.tools@us.bosch.com with a copy of the original receipt or contact us at 1-877-BOSCH99 (1-877-267-2499) from Monday through Friday, 7 a.m. to 7 p.m. CST.
                • Verified Purchase
                • Verified Purchase
                • Verified Purchase
                Cut through cultured marble easily....
                Cut through cultured marble easily.
                • Verified Purchase
                Quick Change Mandrel
                [This review was collected as part of a promotion.] Great product - very dependable. I purchase over 100 of these a year for the company I work for and have never had to report any issues them.
                  • Recommended
                  • Verified Purchase
                  Worked even better than expected....
                  Worked even better than expected.
                  • Verified Purchase
                  • Verified Purchase
                  Worked great, easy to replace hole saws...
                  Worked great, easy to replace hole saws
                  • Verified Purchase
                  Showing 1-10 of 39 reviews