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Mild Steel Box Sections

  UK's Leading Supplier of Cut To Size Materials

Mild steel box sections are hollow metal profiles with a sturdy square or rectangular cross-section ideal for structural framing and fabrication. The tubular shape provides strong resistance to torsion and bending forces, used for applications such as frames, supports, enclosures, packaging, furniture and more. These provide excellent weldability and machinability, versatile fixing options, and are available in standard lengths or custom cut-to-size. We supply a wide range of square and rectangular sizes, with thicknesses from 1.2mm to 150mm. Order today with free custom cutting and fast delivery.

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385,000+
Orders Shipped
1.8million
Pieces Cut to Size
9,000+
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385k+
Orders
1.9mil
Pieces Cut
9k+
5* Reviews
Mild Steel Box Section
75mm x 50mm x 3mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
50mm x 25mm x 3mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
50mm x 30mm x 3mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
60mm x 40mm x 3mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
80mm x 40mm x 3mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
120mm x 80mm x 5mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
20mm x 20mm x 2mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
25mm x 25mm x 2mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
20mm x 20mm x 2.5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
25mm x 25mm x 2.5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
30mm x 30mm x 2.5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
40mm x 40mm x 2.5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
25mm x 25mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
30mm x 30mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
40mm x 40mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
50mm x 50mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
60mm x 60mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
80mm x 80mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
100mm x 100mm x 3mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
50mm x 50mm x 4mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
50mm x 50mm x 5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
70mm x 70mm x 5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
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(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
90mm x 90mm x 5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
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(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
100mm x 100mm x 5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
120mm x 120mm x 5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
150mm x 150mm x 5mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
120mm x 120mm x 8mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
100mm x 100mm x 10mm Mild Steel Square Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
150mm x 100mm x 5mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Mild Steel Box Section
160mm x 80mm x 5mm Mild Steel Rectangular Box Section
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20 reviews
Rated 4.4 out of 5 stars
5 stars
(15)
4 stars
(2)
3 stars
(1)
2 stars
(1)
1 star
(1)

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Rectangular sections in the warehouse
Box sections
Box sections

Mild Steel Box Section FAQs

How strong is a mild box section?

Mild steel box sections can provide high strength when using a thicker material and larger sizes, owing to their closed section with high resistance to bending and torsional forces. The strength increases with thickness and section size due to higher yield strength. Yield strength ranges from about 250 MPa for lower-grade steels up to about 350 MPa for higher grades.

Are mild steel box sections stronger than I beams?

The strength of the box section and I-beam sections depends on their specific dimensions and the direction of the applied load. In some cases, box sections can offer greater torsional (twisting) strength due to their closed shape, while I-beams are often preferred for their superior bending strength, making them a common choice in structural applications like beams and columns.

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Based on 12334 reviews
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Really easy to order
Really easy to order. Shelves all fit perfectly.
Deb,

3 hours ago

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New shed windows
I ordered 6 perspex windows for my shed and they were perfectly cut and packaged. Thank you!
Mr Cave,

6 hours ago

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Great service
Great service, delivery and packaging and a fantastic product not installed into our kitchen.
Doug Potkin,

8 hours ago

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Cannot fault the service or the quality…
Cannot fault the service or the quality of the wood. Instruction’s were clear and precise (just make sure you get your measurement spot on, before ordering!) it’s been so good will be using them again when I plan on decorating the bedroom.
Nathan,

15 hours ago

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Very happy with quality
Very happy with quality and fast service!
Margarita,

16 hours ago

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Cutmy
Cutmy, great communication although the couriers were poor.
Alan Foster,

16 hours ago

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Good quality product
Good quality product, delivered quickly and well packaged. Would definitely recommend this company.
Ruth,

17 hours ago

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Great product
Great product, quick delivery and very well packaged, very pleased :)
CRD,

18 hours ago

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Gret quality and accuracy
Gret quality and accuracy. Reasonable timescale.
Peter Mercy,

18 hours ago

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Easy to order good delivery and…
Easy to order good delivery and excellent item
Glenn Foyster,

19 hours ago

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desk tops
Ordered desk tops for my son, extremely happy with them.
Sophie Mclean,

19 hours ago

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Excellent Service
I was very impressed with the attention to detail. My measurements were checked and it turned out to be an error in my part. Delivery was extremely well packaged and the exact size I needed after the sizes were amended.
Gordon,

20 hours ago

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Great product
Great product. Came quickly and looks great
Craig,

21 hours ago

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GreatProduct!
Easy to use web site, great product. Easy delivery by the courier.
Simon James,

22 hours ago

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Great service
Great service, I used them for some replacement windows in a playhouse shed. Couldn't be happier AAA+++
Peter M,

22 hours ago

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Good price arrived quickly
Good price arrived quickly
Guest,

23 hours ago

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Really easy to order
Really easy to order, items arrived on time and in good condition as usual
Michael Pickles,

1 day ago

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All good
All good, wood well cut, properly packaged, delivered as agreed, would use again
Gerry H,

1 day ago

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MDF panelling made easy
Ordered MDF panelling. The ordering process was easy, and the panelling was well packaged and labelled which simplified the installation greatly. Take a tip from me - don’t be a cheapskate - if you’re going to paint then buy it primed and save yourself an extra step. Highly recommended.
KENNETH MILLER,

1 day ago

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Quality product…
Product is really good and delivery driver was extremely helpful
Tab,

1 day ago