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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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300k+
Orders
1.5mil
Pieces Cut
7k+
5* Reviews
Mild Steel Box Section
75mm x 50mm x 3mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
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(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
50mm x 25mm x 3mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
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(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
50mm x 30mm x 3mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
60mm x 40mm x 3mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
80mm x 40mm x 3mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
120mm x 80mm x 5mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
20mm x 20mm x 2mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
25mm x 25mm x 2mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
20mm x 20mm x 2.5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
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Mild Steel Box Section
25mm x 25mm x 2.5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
30mm x 30mm x 2.5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
40mm x 40mm x 2.5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
25mm x 25mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
30mm x 30mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
40mm x 40mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
50mm x 50mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
60mm x 60mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
80mm x 80mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
100mm x 100mm x 3mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
50mm x 50mm x 4mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
50mm x 50mm x 5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
70mm x 70mm x 5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
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(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
90mm x 90mm x 5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
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(5)
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(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
100mm x 100mm x 5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
120mm x 120mm x 5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
150mm x 150mm x 5mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
120mm x 120mm x 8mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
100mm x 100mm x 10mm Mild Steel Square Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
150mm x 100mm x 5mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
4 stars
(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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Mild Steel Box Section
160mm x 80mm x 5mm Mild Steel Rectangular Box Section
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7 reviews
Rated 4.4 out of 5 stars
5 stars
(5)
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(1)
3 stars
(0)
2 stars
(1)
1 star
(0)

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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 8747 reviews
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Perfect
I’ve order bit wrong shade but otherwise cut perfectly and delivered quickly with no quality issues.
CollectPlus Customer,

2 hours ago

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Excellent product quality
Excellent product quality, well packaged and great price
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2 hours ago

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Really good reliable company. Highly recommended.
I used them quite a few times while refurbishing a kitchen. Outstanding service and outstanding products. Everything was first class. The delivery company they use are not great - just left packages propped up against front door. All in all though - 5 stars.
Derek Janes,

3 hours ago

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Fantastic product
Fantastic product, many thanks. Would use again !!
Sue Thompson,

3 hours ago

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Excellent product.
The product is excellent. The sizing and cutting to size is very useful. Be cautious of the website, it is a nuisance in that if you go back to review anything it re-sets to its default setting. You need to be careful that it hasn't changed anything or you will find yourself paying £30 for a 100mmx 50mm piece of material!
Ian Morris,

6 hours ago

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Excellent good quality product
Excellent product was exactly what I was looking for to repair broken glass panels from my Greenhouse. Have never used Shatterproof window panels before very easy to apply to Greenhouse fitted perfectly and very sturdy and competitive price. Very satisfied with product and service. All goods was well packaged.
Emcg,

8 hours ago

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Will use again
Quick delivery. Very well packaged. Accurately and cleanly cut. Thank you.
Bryan Harral,

9 hours ago

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easy to order and fast delivery
easy to order and fast delivery
Chris Kahle,

13 hours ago

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Great product
Great product. Arrived quickly.
Kenneth Lowe,

21 hours ago

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Bathroom splash backs
The parts I ordered where perfectly sized and did the job I wanted them to do.
Mrs Waddingham,

21 hours ago

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Good service and excellent quality…
Good service and excellent quality product
Brian ,

23 hours ago

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Fast efficient service and quality…
Fast efficient service and quality product
J murray,

23 hours ago

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Ordered
Ordered Confirmed Delivered !! What more can you want just need the weather to be dry to use it. Cannot blame you for that !
Miss Louise Hizzett,

1 day ago

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Very pleased with the service provided.
Very pleased with the service provided. Easy to order and pay for and was perfect on delivery.
Mrs K Taylor,

1 day ago

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Accurate sizes
Accurate sizes, prompt delivery and reasonable price
Mr John Isherwood,

1 day ago

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Made to specification and promptly…
Made to specification and promptly delivered
Steve Dunn,

1 day ago

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Pieces were cut exactly to dimensions…
Pieces were cut exactly to dimensions and delivered very well packed.
M Bacon,

1 day ago

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Easy to use the website and place my…
Easy to use the website and place my order.
Karen and Paul,

1 day ago

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First Class Service
Love their products and always good service.
Gary Stirk,

1 day ago

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Superb quality and service
Superb quality and service. Bespoke measurements were spot on.
Rob,

1 day ago