Short answer: National Enamel Gloss II M.I.O. is a fast-drying alkyd gloss enamel pigmented with micaceous iron oxide, for external structural steel, cranes, towers, bridges and pipelines in mild industrial environments. National describes a tough, high-gloss film with good abrasion resistance and a barrier against water vapour. Apply two coats of 35 microns over Zinc Phosphate Primer and M.I.O. Undercoat (150 microns total). It covers 13 to 17 m² per litre, is touch dry in 1 hour and recoats in 8 hours at 30°C.
Where it fits
This is the finish coat of National’s MIO system for exposed steel. It shares Gloss II’s fast-drying alkyd base but adds micaceous iron oxide, and it is light grey only. Compare it with the other glossy alkyds National makes:
| Enamel | Listed for | Colours | Recoat at 30°C |
|---|---|---|---|
| Enamel Gloss II M.I.O. | External steel structures, mild industrial | Light grey | 8 h |
| Synthetic Enamel Gloss II | Metal, wood, masonry; equipment and vehicles | Shade card | 8 h |
| Synthetic Enamel Gloss I | Walls and steel, general purpose | Shade card | 18 h |
| Industrial Quick Drying Enamel | Steel, pipes, scaffolding, machinery | Shade card | 4 to 6 h |
Key facts
| Type | Fast-drying alkyd enamel with micaceous iron oxide, single pack |
| Exposure | External |
| Finish and colour | Gloss, light grey |
| Volume solids | 52 ± 2% |
| Specific gravity | 1.3 ± 0.05 |
| Spreading rate | 13 to 17 m² per litre (theoretical) |
| Film per coat | 30 to 40 microns dry (58 to 77 wet) |
| Drying at 30°C | Touch dry 1 hour; recoat 8 hours; hard dry 24 hours |
| Application | Airless spray (2200 psi, tip 0.015 to 0.018 inch), air spray (50 psi) or brush |
| Thinning | Airless 5 to 10%, air 10 to 15%, brush 10%, with National G.P. Thinner |
| Flash point | 38°C |
| Shelf life | 18 months, sealed |
The system and timeline
| Step | Product | Dry film | Earliest next coat (30°C) |
|---|---|---|---|
| Prepare | Degrease; blast to Sa 2.5 or clean to St 2 | Prime the same day | |
| 1 | Zinc Phosphate Primer | 40 µm | 10 h |
| 2 | M.I.O. Undercoat | 40 µm | 14 h |
| 3 | Enamel Gloss II M.I.O. | 35 µm | 8 h |
| 4 | Enamel Gloss II M.I.O. | 35 µm | Hard dry 24 h |
| Total | 150 µm | At least 32 h of coating time | |
What the numbers mean
- Coverage = 520 ÷ 30 ≈ 17.3 and 520 ÷ 40 = 13 m² per litre, matching the sheet.
- Wet film for a 35-micron coat = 35 ÷ 0.52 ≈ 67 microns.
How much to buy
| Steel area | Zinc Phosphate × 1 | MIO Undercoat × 1 | Gloss II MIO × 2 |
|---|---|---|---|
| 100 m² | about 8.7 L | about 8.3 L | 11.8 to 15.4 L |
| 500 m² | about 43.5 L | about 41.7 L | 59 to 77 L |
Frequently asked questions
Is it for harsh marine or chemical sites?
National lists it for mild industrial environments. For heavy duty, its specifier uses an epoxy system of 300 to 350 microns with an epoxy or polyurethane topcoat; see steel painting systems and Nationalthane.
Can I get it in other colours?
The sheet lists light grey only. For coloured gloss over the same primer, use Synthetic Enamel Gloss II, which the MIO Undercoat sheet also accepts.
Buy in Sharjah and Dubai
Al Tashteb Al Saree is an authorised National Paints retailer in Bu-Tina, Sharjah. Message us on WhatsApp for the full MIO system.
Sources
- National Enamel Gloss II M.I.O. data sheet (PDF)
- National M.I.O. Undercoat data sheet (PDF)
- National Zinc Phosphate Primer data sheet (PDF)
- National Paints surface preparation guide, Sec. A-2 (PDF)
- National Paints systems specifier (PDF)
All via AEC Online, retrieved 4 November 2026. Quantities and timings are our own calculations. The main image is illustrative.
