304
General purpose
Widely used for architectural frames, handrails, equipment guards, furniture and general fabrication.
Product form hub · Rectangular tube
Stainless Steel Rectangular Tube
Specify stainless steel rectangular tube by grade, outside dimension, wall thickness, finish, length and fabrication requirements. This page gives buyers a practical route from common market sizes to a quote-ready specification.
304 / 304L / 316 / 316L
ASTM A554 route
Mill, brushed or polished finish
Rectangular hollow section · product visual
Common grades304 / 304L / 316 / 316L
Typical market size20 × 10 to 200 × 100 mm
Typical wall1.0 to 5.0 mm
Build the specification
01Choose grade
02Set width × height
03Set wall thickness
04Choose finish
05Confirm length / fabrication
06Send RFQ
Product overview
What to define before buying stainless steel rectangular tube
Rectangular tube is normally purchased by outside width × outside height × wall thickness. Grade, finish, corner geometry and fabrication route can be just as important as the nominal size.
Material304 / 304L
General architectural, fabrication and indoor-to-moderate corrosion service.
Material316 / 316L
Often selected where chloride exposure or a more demanding corrosion environment is expected.
GeometryWidth × height × wall
Specify outside width × outside height × wall, for example 50 × 25 × 2.0 mm.
FinishMill to decorative
Mill, satin / No.4, hairline and mirror-type finishes are common market options.
M03 · Grade selection
Choose the grade from the service environment first
Do not choose rectangular tube only by appearance. Corrosion environment, welding, cleaning chemicals, temperature and fabrication route should drive grade selection.
304L
Weld-friendly low carbon
Common when welded fabrication is important and a low-carbon 304 route is preferred.
316
Higher corrosion resistance
Common for more demanding outdoor, coastal or chemical-service environments.
316L
Corrosion + welding route
Frequently specified when both welding and improved chloride resistance are important.
M04 · Technical data
Common stainless steel rectangular tube size reference
The table below uses common market dimensions for stainless rectangular tube. Treat it as a buying reference, not as a promise of current stock. Confirm exact width, height, wall, length and finish in the RFQ.
| Outside size | Common wall options | Typical grade routes | Typical finish routes | Buying note |
|---|---|---|---|---|
| 20 × 10 mm | 1.0 / 1.2 / 1.5 mm | 304 / 304L | Mill / brushed | Light trim, frames and decorative fabrication |
| 25 × 15 mm | 1.0 / 1.2 / 1.5 / 2.0 mm | 304 / 304L / 316L | Mill / No.4 / hairline | Furniture, guards and compact frames |
| 30 × 20 mm | 1.2 / 1.5 / 2.0 mm | 304 / 304L / 316L | Mill / No.4 / hairline | General decorative and light fabrication |
| 40 × 20 mm | 1.2 / 1.5 / 2.0 / 3.0 mm | 304 / 304L / 316L | Mill / No.4 / hairline | Common railing, furniture and frame size |
| 50 × 25 mm | 1.2 / 1.5 / 2.0 / 3.0 mm | 304 / 304L / 316 / 316L | Mill / No.4 / hairline | Widely used rectangular hollow section |
| 60 × 30 mm | 1.5 / 2.0 / 3.0 mm | 304 / 304L / 316L | Mill / brushed | Equipment frames and architectural fabrication |
| 80 × 40 mm | 1.5 / 2.0 / 3.0 / 4.0 mm | 304 / 316L | Mill / brushed | Heavier frames and support structures |
| 100 × 50 mm | 2.0 / 3.0 / 4.0 mm | 304 / 316L | Mill / brushed | Confirm corner radius and straightness |
| 120 × 60 mm | 2.0 / 3.0 / 4.0 / 5.0 mm | 304 / 316L | Mill / brushed | Common heavier fabrication route |
| 150 × 75 to 200 × 100 mm | 2.0–5.0 mm market range | 304 / 316L | Primarily mill / brushed | Availability becomes more supplier-specific |
Market reference range: stainless rectangular tube is commonly listed from about 20 × 10 mm up to 200 × 100 mm with wall thicknesses around 1.0–5.0 mm and 6 m commercial lengths. ASTM A554 covers welded stainless mechanical tubing in rectangular, square, round and special shapes; actual commercial availability varies by grade, finish and supplier.
M05 · Dimensions and finish
Define the tube beyond just “rectangular”
A usable purchase specification should state outside width, outside height, wall thickness, length, finish and any fabrication requirement that affects the final fit or appearance.
Dimensions
- Outside width × outside height
- Nominal wall thickness
- Length or cut length
- Corner radius if critical
- Straightness / squareness if project-critical
Surface finish
- Mill finish
- 2B-related strip finish before forming
- No.4 / satin brushed
- Hairline finish
- Mirror-type decorative finish
Fabrication details
- Cut to length
- Square or mitred cut
- Visible-weld appearance requirement
- Protective film if required
- Packaging for cosmetic surfaces
M06 · Selection guide
Match the tube specification to the actual use
Indoor decorative work304 is a common starting point. Prioritize cosmetic finish, corner consistency and scratch protection.
Welded fabrication304L or 316L may be preferred when the fabrication route and corrosion requirements justify a low-carbon grade.
Coastal / chloride exposure316 / 316L is commonly considered before 304, but the real environment and maintenance plan still control selection.
Load-bearing frameDo not assume decorative mechanical tubing is automatically suitable. Confirm the design code, loads, section properties and required certification.
Worked example
Example of a clear rectangular tube specification
A short, explicit specification is easier to review than a request that only says “304 stainless rectangular tube.”
Example only
This is a sample buying format, not a stock promise. Replace each field with the actual project requirement before ordering.
ProductStainless steel rectangular tube
Standard routeASTM A554
Grade304L
Size50 × 25 × 2.0 mm
Length6 m
FinishNo.4 brushed, visible faces protected
Order requirementState quantity, cutting, packaging and document requirements in the RFQ
M08 · Applications
Where stainless steel rectangular tube is commonly used
Architectural frames
Visible frames, partitions, façade details and decorative support structures.
Handrails & balustrades
Rectangular-section rails and frames where clean lines and corrosion resistance are required.
Furniture & displays
Tables, shelving, retail fixtures and stainless framework with brushed or polished surfaces.
Machine guards
Fabricated equipment frames, guard structures and enclosures.
Food equipment frames
Non-product-contact framework where cleanability and corrosion resistance matter.
General fabrication
Welded frames, brackets and custom assemblies across industrial and commercial projects.
Important limitation: ASTM A554 rectangular tubing is a mechanical / ornamental tubing route. Do not assume it is automatically pressure-rated or automatically compliant with a structural design code. For load-bearing, hygienic, pressure or regulated service, confirm the governing project specification before purchase.
M10 · Standards
Standards and purchasing references
Use the actual project standard as the governing requirement. Do not mix a cosmetic rectangular-tube request with a structural or pressure-tube requirement without checking the applicable specification.
Welded stainless steel mechanical tubing. The standard covers square, rectangular, round and special shapes for applications where appearance, mechanical properties or corrosion resistance are required.
Specify the exact alloy designation required by the project rather than relying only on a marketing label such as “marine grade” or “food grade.”
For critical corner radius, straightness, polish, weld-bead appearance, fabrication or inspection, place the requirement directly on the RFQ or drawing.
M11 · FAQ
Stainless steel rectangular tube FAQ
What is the most common stainless steel rectangular tube grade?
304 and 304L are common general-purpose choices. 316 and 316L are often considered when the corrosion environment is more demanding, especially where chlorides are present.
How is rectangular tube size specified?
Use outside width × outside height × wall thickness, for example 50 × 25 × 2.0 mm. Add length, grade, finish and any tolerance or fabrication requirement.
Is stainless steel rectangular tube seamless or welded?
Most common architectural and mechanical stainless rectangular tube is welded and commonly specified to ASTM A554. If a project needs another manufacturing route, state it explicitly.
What finishes are available?
Common market finishes include mill, satin / No.4, hairline and mirror-type decorative finishes. Availability depends on grade, size, wall and supplier process.
Can rectangular tube be used as structural tubing?
It can be used in frames, but the engineering requirement must be checked separately. Do not assume an ornamental or mechanical tubing specification automatically satisfies a structural code or load requirement.
Product details
What buyers usually verify visually
Replace these three visual areas with your own rectangular tube product, surface and packing images when the first-party media is ready.
Tube geometryWidth × height proportions, corners and weld-seam condition
Surface finishMill, satin / brushed, hairline or decorative finish
Packing & protectionProtect visible surfaces and edges for delivery
Rectangular tube resources
Continue from technical research to purchase
Material hub
Stainless Steel
Review the parent material hub and related stainless steel product forms.
Open stainless steel hub → Technical Technical ResourcesUse standards, comparisons and engineering references to clarify the purchase specification.
Open technical resources → Sourcing Request a QuoteMove from a reviewed specification to a purchasing conversation.
Open RFQ page →M13 · Technical reference
Reference basis for this rectangular tube guide
The page uses ASTM A554 scope information plus common commercial rectangular-tube size patterns. Project-specific requirements and actual supply availability should always be confirmed before order placement.
M14 · RFQ
Request a technical quote
For a faster review, include the grade, width × height, wall thickness, finish, length, quantity, destination and any special fabrication or document requirement.
- Grade / material designation
- Outside width × height × wall thickness
- Finish and visible-surface requirement
- Length / cutting requirement
- Quantity and destination