Quick Answer
Read the full coating specification. A duplex system combines hot-dip galvanizing with a paint or powder topcoat. Powder coating alone does not confirm a galvanized base, and appearance does not establish corrosion performance for an individual product.
At a Glance
| Duplex system | Hot-dip galvanized steel plus paint or powder topcoat |
|---|---|
| Before specifying a topcoat | Confirm compatible preparation of the galvanized surface. |
| Product selection | Check the exact item's material, coating process and intended application. |
| Performance evidence | Use product-specific evidence; this general guide provides no product life or corrosion rating. |
Sources: [1] American Galvanizers Association — Duplex Systems
Read the complete finish description
When comparing hardware, check the product specification for the base material, coating process and intended use. Ask for clarification if the description only says galvanized or coated; do not infer a process, coating thickness or performance rating from a photograph.
What is a duplex system?
The American Galvanizers Association describes a duplex system as hot-dip galvanized steel with an additional paint or powder topcoat. The surface must be prepared for the selected topcoat to achieve a successful system.
A powder-coated product is not automatically a duplex product. Confirm that hot-dip galvanizing is actually part of that product's specification before describing it this way.
Sources: [1] American Galvanizers Association — Duplex Systems
Ask questions that match your project
Use the same checklist when comparing products or discussing a custom requirement with a supplier.
- What coating process is specified for this exact item?
- What installation environment is it intended for?
- Are the selected fasteners suitable for that environment and the connected materials?
- What inspection and maintenance guidance is supplied?
Keep product claims specific
A general explanation of a coating technology is not a test report for a particular bracket. Look for evidence tied to the exact product and finish when comparing performance claims. This article does not assign a service life or corrosion rating to SUPCONN products.
Common Questions
Is all powder-coated hardware also galvanized?
No. A powder-coating description does not identify the underlying corrosion-protection system. Check whether galvanizing is specified for the exact product.
What does duplex coating mean here?
It means a paint or powder topcoat applied over hot-dip galvanized steel, with surface preparation appropriate to that topcoat.
Can I infer outdoor service life from the coating's color?
No. Ask for the documented coating system, intended environment, maintenance guidance and any product-specific performance evidence.