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FAMCO SDB square to round HVAC transition Box, galvanized steel
FAMCO SDB square to round HVAC transition Box, galvanized steel
FAMCO Square to Round Transition Box Measurement Guide
Square to round duct transition box, front-facing angle.
Side angle of a square to round duct transition.
Back view of a square to round transition box.

Square to Round Transition Box

(72 customer reviews)

$24.95 – $79.95

  • Quality constructed from heavy-duty 28 gauge galvanized steel
  • Primarily for use to attach a ceiling register to your air supply
  • Can be used in many applications that transition a square duct to round duct
  • Available in a variety of common sizes, see the drop down menu for all sizes available

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SKU SDB Categories ,

Description

The FAMCO SDB square to round HVAC transition Box – diffuser is designed primarily for use to attach a ceiling register to your air supply, but can be used in many applications that transition a square duct to round duct. Quality constructed from heavy-duty 28 gauge galvanized steel. Available in a variety of common sizes, see the drop down menu for all sizes available. The FAMCO SDB square to round HVAC transition box is manufactured by FAMCO in the United States and comes with a 1-year warranty against product defects and workmanship. If you have any questions about this product, please refer to the FAQs above or feel free to contact us.

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Spec Sheet

Print Spec Sheet

Square to Round Transition Box

SKU: SDB

Questions and answers of the customers

    Does the size pertain to the round duct size?
  1. Q Does the size pertain to the round duct size? answer now
    Asked on April 19, 2022 12:26 pm
    A

    Yes, the "size" selection refers to the round hole size. The "dimensions" selection would be for the square part of the box.
    A Yes
    A Yes
    2. I have a 18" Round Plenum, need to adapt to Rectangular plenum. is this made to order ?
  2. Q I have a 18" Round Plenum, need to adapt to Rectangular plenum. is this made to order ? answer now
    Asked on August 23, 2021 3:21 pm
    A

    These products are currently manufactured in our Meridian, Idaho factory - the sizes we are able to manufacture are those shown in the dropdown menu.
    3. Can these be used for a bathroom exhaust fan intake opening where moist air will travel through the vent?
  3. Q Can these be used for a bathroom exhaust fan intake opening where moist air will travel through t...... Read more answer now
    Asked on August 16, 2021 7:55 am
    A

    We would recommend asking your exhaust fan manufacture for their recommended install method.
    4. I'm looking for something like this but without the "box". I need need to connect round flexible duct to a rectangular hole on the main trunk, but with the "box" there's no mating surface (I need flat sides to secure with sheet metal screws). I suppose I could break the welds and hammer the sides flat but do you have a product like I'm describing? I can find them in plastic but would prefer galvanized aluminum. Thanks.
  4. Q I'm looking for something like this but without the "box". I need need to connect round flexible ...... Read more answer now
    Asked on August 12, 2021 7:52 am
    A

    This is not something that we currently supply or manufacture.
    A The magic phrase is Start Collar. You need a start collar, either buy it (somewhere), or watch a YouTube video.
    5. I need a 13"×14"×6"round
  5. Q I need a 13"×14"×6"round answer now
    Asked on July 29, 2021 7:24 pm
    A

    This is not a size we are currently able to manufacture, unfortunately.
    6. I need a 24" x 24" and 14" diameter transition box. Do you have this size? Thanks
  6. Q I need a 24" x 24" and 14" diameter transition box. Do you have this size? Thanks answer now
    Asked on June 16, 2021 11:48 am
    A

    Yes - this is a size we are currently able to manufacture, you can select these dimensions in the dropdown.
    7. If I order today ..which one is the delivery date? thanks
  7. Q If I order today ..which one is the delivery date? thanks answer now
    Asked on June 12, 2021 12:58 pm
    A

    Current manufacturing and shipping estimates are given in the shopping cart and at checkout.
    8. I need a 10"w x 3-1/4 to a "6 inch-round
  8. Q I need a 10"w x 3-1/4 to a "6 inch-round answer now
    Asked on May 18, 2021 5:49 pm
    A

    This is not a size we currently manufacture, unfortunately.
    9. Do you make w 16”. L18” round 14. Duct adapter
  9. Q Do you make w 16”. L18” round 14. Duct adapter answer now
    Asked on May 2, 2021 12:06 pm
    A

    We currently only manufacture the sizes shown in the dropdown menu
    10. Do you make these in 18Wx18Lx12D
  10. Q Do you make these in 18Wx18Lx12D answer now
    Asked on April 25, 2021 1:05 pm
    A

    Yes - all sizes available can be selected in the dropdown on the product page.
    11. Could we order this for a custom size box of 16 x 25 in square and 8-inch diameter circle? Thank you.
  11. Q Could we order this for a custom size box of 16 x 25 in square and 8-inch diameter circle? Thank ...... Read more answer now
    Asked on October 25, 2020 11:17 pm
    A

    We currently only offer customization on volume runs with a total value greater than $5,000

72 reviews for Square to Round Transition Box

5.0
Based on 72 reviews
5 star
98
98%
4 star
1
1%
3 star
0%
2 star
0%
1 star
0%

  1. Chris –

    Good quality

    Pretty basic square to round transition, but very well made. Ordering was easy and it got here pretty quick. The only problem was on my end, I ordered the wrong size. I needed a 12″ instead of the 14″. Oh well, I can always let my boss have them and consider it another example of the woodworkers maxim: “Measure twice. Cut once.”

  2. Christopher T. (verified owner) –

    I had a question about dimension, they responded within an hour and order was made, item arrived a week later just as I had hoped. Great experience.

  3. R ALLEN (verified owner) –

    The part looks nice and it was built and shipped quickly!

  4. Anonymous (verified owner) –

  5. Shannon (verified owner) –

    This arrived in perfect condition and fit exactly how I needed.

  6. Andrew (verified owner) –

    Thanks for making these available and easy to order. Great quality. Good shipping process.

  7. Hugh Siebenthall (verified owner) –

    My order was small and of little consequence to your overall operation. You followed through precisely as stated. Thank you and your entire team.

  8. Tim Thompson (verified owner) –

  9. Mark Nuhfer (verified owner) –

    Exactly what I ordered
    Just a little expensive with the shipping being about the same price as the product.
    But I knew I needed it.
    The quality is there long after the price is gone.

  10. Anonymous (verified owner) –

  11. john d. (verified owner) –

    Quick and easy to order. Arrived in perfect condition. Good price.

  12. John B. (verified owner) –

  13. tony ozark (verified owner) –

    Perfect!

  14. Roy Oldaker (verified owner) –

  15. Dan (verified owner) –

  16. Jose Gonzales (verified owner) –

    Thank you! It was both put together and priced very well!

  17. Richard Plenert (verified owner) –

  18. John Garbarino (verified owner) –

    Great company ford hard to find stuff fast shipping

  19. Anonymous (verified owner) –

  20. mark t. (verified owner) –

    The transition box I ordered fit perfectly around my water to air heat exchanger. And very good build quality.

  21. Nick D. (verified owner) –

  22. Josefa Barreiro (verified owner) –

  23. Anonymous (verified owner) –

  24. Josef (verified owner) –

    Quality product, no problem with any phase of this order. Thanks!!!!!

  25. Kendall Marks (verified owner) –

    Excellent value, fast delivery

  26. Joseph Firrantello (verified owner) –

    Product was perfect for my needs. Received quickly.

  27. Anonymous (verified owner) –

  28. Matthew T. (verified owner) –

    Perfect!!!! Very happy!!! Will buy here again!!

  29. Hector cruz (verified owner) –

    👍

  30. Andrew (verified owner) –

    Great craftsmanship

  31. James G. (verified owner) –

    Awesome! This has been a life saver. I bought this to help redirect heat from the furnace in my RV. It used to blow straight onto the thermostat so it never got warm inside and the furnace kept kicking on and off. Now i’ve successfully redirected all the heat and it works like it should. Haven’t burned the place down yet either!

  32. Jessica (verified owner) –

  33. Glenn Fulmer (verified owner) –

    Great fit and great construction.

  34. Mike M. (verified owner) –

    Beautiful product, arrived quickly!

  35. Ralph P. (verified owner) –

    The product was excellent quality and fit perfectly

  36. Ralph (verified owner) –

    Well made u band exactly what I wanted.

  37. Bud C. (verified owner) –

    As advertised, shipped promptly, very high quality product. Shipping cost was high but would buy from Famco again.

  38. Bennie Keisling (verified owner) –

    Good quality & fast delivery!

  39. Ryan (verified owner) –

    I put up new drywall for home renovations and in the process needed to move my return line for the a/c. The dimensions of my old return box were too large for the vent cover I needed, so I ordered a custom transition box from FAMCO. It arrived exactly as what I ordered and made the job easy to finish. And it was quite a bit cheaper than other competitors. I will definitely keep FAMCO in mind for any projects in the future.

  40. Jake M. (verified owner) –

    Fast shipping and exactly what I was looking for. Came well packaged and the manufacturing was top quality. Thank you

  41. Steve Chayer (verified owner) –

    Trustworthy. Have confidence in this company for delivery times and quality of product.

  42. Gregory R. (verified owner) –

  43. Wayne Cox (verified owner) –

    I love these people at Famco. They have never let me down. They always ship when they say they are going to ship, I highly recommend them.

  44. Armand (verified owner) –

    The transition box was very well made, and arrived in a timely manner.

  45. Peter Saloufakos (verified owner) –

    Fits perfect.

  46. Paul Scholer (verified owner) –

  47. Bart Domingue (verified owner) –

    Very satisfied

  48. Gordon Rhodes (verified owner) –

  49. Loreimy Panchis (verified owner) –

  50. Anonymous (verified owner) –

    Custom product not found elsewhere. Exactly what I needed.

  51. Alexis B. (verified owner) –

  52. Kevin K. (verified owner) –

  53. Herbert West (verified owner) –

  54. Charles R. (verified owner) –

  55. Robert (verified owner) –

    Dimensions are true as shown online. Well made. My project required a flat black finish. The FAMCO box painted up well. I primed before applying the final coat.

  56. Jim G. (verified owner) –

    Well made product, worked perfectly

  57. Anonymous (verified owner) –

  58. David S. (verified owner) –

  59. Clay (verified owner) –

    Fit perfectly with high quality fabrication.

  60. Pat Urlacher (verified owner) –

    Great product fitment was right on the money.👍👍👍👍

    Image #1 from Pat Urlacher

  61. David Watson (verified owner) –

    Well made and dimensions were spot on. Replaced old hood vent, which had a 6″ square exit. New vent has 6″ round. And slightly offset.

    Image #1 from David Watson
    Image #2 from David Watson
    Image #3 from David Watson
    Image #4 from David Watson

  62. Brian (verified owner) –

    Item exactly as described/ordered.

  63. Anonymous (verified owner) –

  64. Anthony (verified owner) –

  65. Jason McLeod (verified owner) –

  66. Andrew R. (verified owner) –

  67. George Bowersox (verified owner) –

  68. Michael (verified owner) –

    It’s made to perfection!

  69. MICHAEL B. (verified owner) –

    Transition from round to square went perfect!

  70. MICHAEL B. (verified owner) –

  71. Andy –

    Great product and pricing and the quality of workmanship is the best

  72. Paul (verified owner) –

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OUR PRODUCT GUARANTEE

FAMCO prides itself on Quality Built Products manufactured from quality raw materials. All products are guaranteed to be free of defective material or workmanship for a period of one year from the date of delivery. During the guarantee period, if any parts prove defective, they will be replaced free of charge. Please click here to review a complete version of our limited warranty.
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