DEVCON FL-20
Harmonization Code : 3208.20.90 | Paints and varnishes that are dispersed or dissolved in a non aqueous medium

Main features
- 30 to 120-Minute Moisture Cure
- Multi-Substrate Flexane Adhesion Promotion
- One-Part No-Mix Primer
Product Description
Devcon® FL-20 Primer is a one-part, moisture-cure adhesion-promoting primer used with Devcon® Flexane® products on concrete, wood, rubber, fiberglass, PVC, cured polyurethane, and cured epoxy surfaces. The orange, low-solids primer requires no mixing and provides a 30–120 minute cure time. Depending on the substrate, one or more coats may be applied before top coating with Flexane within the documented application window. Suitability must be evaluated for the intended substrate, preparation method, application, and process conditions.
Key features
- One-part moisture cure: Requires no mixing and cures in 30–120 minutes under documented conditions.
- Multi-substrate priming: Intended for concrete, wood, rubber, fiberglass, PVC, cured polyurethane, and cured epoxy.
- Flexane system compatibility: Conditions applicable surfaces before the application of Devcon® Flexane® products.
Applications / Suitable for
- Priming concrete and wood before Flexane application
- Priming gum rubber, neoprene, and cured polyurethane
- Priming fiberglass, PVC, and cured epoxy surfaces
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Additional Information
As-supplied / before-processing properties
Typical physical and processing properties of Devcon® FL-20 Primer. Typical technical data are not intended for specification purposes.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Product form | One-part moisture-cure primer | — | Mixing is not applicable |
| Color | Orange | — | Typical |
| Solids by volume | 3.70 | % | Typical |
| Coverage | 10 (0.93) per 4 oz | ft² (m²) | At 5 mils (0.13 mm) |
| Cure time | 30–120 | minutes | Higher humidity increases cure time |
| Top-coating window | 30–120 | minutes | Minimum 30 minutes and maximum 2 hours before top coating with Flexane |
| Storage temperature | 70 (21) | °F (°C) | Store at room temperature |
After-processing / final-state properties
Typical adhesion results after seven days of cure at 75 °F (24 °C). Results are substrate- and test-configuration-specific and are not intended for specification purposes.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Adhesion on concrete | >50 (>8.8) | pli (N/mm) | One coat; cured 7 days at 75 °F (24 °C) |
| Adhesion on cured Flexane | >50 (>8.8) | pli (N/mm) | One coat; cured 7 days at 75 °F (24 °C) |
| Adhesion on fiberglass | >50 (>8.8) | pli (N/mm) | One coat; cured 7 days at 75 °F (24 °C) |
| Adhesion on polyester | >25 (>4.4) | pli (N/mm) | One coat; cured 7 days at 75 °F (24 °C) |
| Adhesion on rubber | >50 (>8.8) | pli (N/mm) | One coat; cured 7 days at 75 °F (24 °C) |





















