Short answer: 2B is the common smooth, lightly reflective cold-rolled mill finish; BA or 2R is bright annealed and more reflective; No. 4 is a directional brushed or polished finish; mirror is a highly polished decorative surface. Finish names alone are insufficient for visual matching, so buyers should approve a physical reference sample.
This guide is written for stainless steel buyers, sourcing teams, engineers and product manufacturers. The purpose is not to declare one universal winner, but to turn a broad material question into a specification that a mill or service center can quote, process and inspect consistently.
Quick Comparison
| Option | Key point | Typical use or decision |
|---|---|---|
| 2B | Smooth, dull-to-lightly reflective mill finish | Fabrication, tanks, hidden components |
| BA / 2R | Bright, smooth annealed finish | Appliances, reflectors, decorative parts |
| No. 4 / brushed | Directional grain | Kitchen panels, elevators, architecture |
| Mirror | Highly polished reflection | Decorative trim, signage, premium interiors |
The table is a starting point. Actual performance depends on the governing standard, delivered condition, dimensions, surface finish, fabrication route and service environment. Commercial names should never replace a complete purchase specification.
What Buyers Should Evaluate
- Define grain direction, roughness or polishing route where appearance matters.
- Approve a master sample under agreed lighting.
- Select protective film compatible with laser cutting, bending and storage.
For production orders, share the end use rather than requesting a grade or finish in isolation. A supplier can then review corrosion exposure, forming severity, welding, visual requirements and packing before material is cut. This early review is usually less expensive than correcting a rejected shipment or unstable production trial.
Common Purchasing Mistakes
- Expecting No. 4 from two suppliers to look identical
- Specifying mirror without an acceptance standard
- Ignoring finish direction when cutting nested parts
These mistakes are avoidable when drawings, approved samples, inspection methods and certificate requirements are agreed before production. For visual products, retain a signed master sample. For functional dimensions, define where and how measurements will be taken.
Recommended RFQ Wording
State base grade, mill finish, secondary finish, abrasive or roughness target, grain direction, film type, visual acceptance sample and permissible defects.
Also include order quantity, acceptable quantity variation, destination, required delivery date and whether partial shipments are allowed. If a requirement is critical, make it measurable and place it on the purchase order rather than only in an email conversation.
How Still Steel Supports the Project
Still Steel supplies stainless steel coil, strip and sheet and provides slitting, cut-to-length, brushing, polishing and protective-film services. We can compare available mill material with your drawing, prepare trial quantities and preserve heat-number traceability through service-center processing.
Send the grade, dimensions, annual volume and application to vip@still-steel.com, or discuss the requirement on WhatsApp.
Frequently Asked Questions
Is BA the same as mirror?
No. BA is a bright mill finish; mirror normally requires additional polishing and a defined visual standard.
Which finish hides scratches best?
A controlled brushed finish is often more forgiving than a mirror surface, although deep scratches remain visible.
Does finish affect corrosion resistance?
Yes. Smoother, cleaner surfaces generally resist deposit retention and corrosion initiation better than rough surfaces.
Technical References
Reference documents support general selection and fabrication principles. The final material decision must follow the applicable contract, standard, regulation and engineering review for the specific product.