US Chemical & Plastics
USC 42-4 Fast Activator 1 qt Liquid 4:1 Mix - Use with 40 4.2 VOC Glamour Clearcoat
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Hazardous material · Liquid
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Ground freight only (UPS/FedEx). Cannot ship via Air, USPS, or to PO boxes. APO/FPO addresses excluded.
WARNING: Cancer & Reproductive Harm
California Pro65 Warning: Cancer and Reproductive Harm
Tap for details → P65Warnings.ca.gov
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Overview
Built for the booth.
A premium glamour clearcoat that delivers on performance, durability and appearance. Recommended two coat coverage results in a beautiful high-gloss finish. National rule compliant.
USC® 42-4 Fast Activator is a liquid catalyst formulated for use with 40-4.2 VOC Glamour urethane clearcoat. It provides rapid activation in a 4:1 mix ratio, delivering a pot life of more than five hours at 78 °F (25.6 °C) and flash times of 8-10 minutes between coats at 72 °F (22 °C), allowing efficient workflow in multi-coat applications.
The activator offers coverage of approximately 610 sq ft per quart at a film thickness of 1.0 mil, with a solids content of 45 %. It is compatible with e-coat and plastic substrates, ensuring strong adhesion and consistent cure on common automotive body shop materials.
Safety handling requires a "Warning" signal word designation. Use appropriate personal protective equipment-including eye protection, gloves, protective clothing, and a respirator-and ensure adequate ventilation. Follow standard first-aid procedures for inhalation, skin, eye, or ingestion exposure as outlined in the SDS.
Why Pros Choose US Chemical & Plastics USC
- Two coat coverage
Application Guide
- Mix USC® 42-4 Fast Activator with the 40 4.2 VOC Glamour Urethane Clearcoat at a ratio of 4 parts clearcoat to 1 part activator. The mixed material has a pot life of greater than 5 hours at 78 °F (25.6 °C).
- Apply the first coat using the recommended spray technique for urethane clearcoats.
- Allow a flash time of 8-10 minutes between coats when applying additional layers, maintaining ambient conditions around 72 °F (22 °C). Continue coating until coverage is achieved; each subsequent coat follows the same flash interval.
Compatibility
Compatible paint systems: Urethane, Clearcoat.
Specifications
| Part No. | 42-4 |
|---|---|
| Product Line | USC |
| MFR Model | 42-4 |
| Standard/Approvals | California Pro65 Warning: Cancer and Reproductive Harm |
| Manufacturer | US Chemical & Plastics |
| UPC | 037307004240 |
| Brand | USC® |
| Rubberized | No |
| Container Size (qt) | 1 |
| Form | Liquid |
| Mixing Ratio | 4:1 |
- Mix Ratio
- 4:1
- Pot Life
- > 5 hours @ 78 °F / 25.6 °C
- Flash Time
- 8-10 min between coats @ 72 °F / 22 °C
- Coverage
- 610 sq ft @ 1.0 mil (solids 45 %)
- Compatible Substrates
- e-coat, plastic
About US Chemical & Plastics
US Chemical & Plastics is a trusted manufacturer of professional auto body and refinish products used by collision repair shops and restoration specialists across North America.
Frequently Asked Questions
What substrates are compatible with USC® 42-4 Fast Activator?
The activator is formulated for use on e-coat and plastic surfaces.
How much area can one quart cover?
One quart provides approximately 610 sq ft of coverage at a film thickness of 1.0 mil (45 % solids).
What personal protective equipment is required when handling this product?
PPE must include eye protection, chemical-resistant gloves, protective clothing, and a respirator suitable for organic vapors.
How long is the pot life and flash time for this activator?
The mixed product has a pot life of greater than 5 hours at 78 °F (25.6 °C). Flash time between coats is 8-10 minutes at 72 °F (22 °C).
Documents & Safety
Warning - This fast activator is highly toxic if inhaled or swallowed, can cause severe skin burns, serious eye injury, and is flammable. It also poses long-term risks such as cancer, organ damage, and reproductive effects. Wear safety goggles or face shield, chemical-resistant gloves, protective clothing, and a suitable respirator when handling. Always refer to the full SDS before use.
Why Buy from autofxmart
- Authorized distributor — authentic, factory-fresh stock.
- Fast US shipping — most orders ship within 1 business day.
- 30-day returns — buy with confidence.
- Pro-shop pricing — bulk discounts available on request.
- Expert support — questions? Email us at support@autofxmart.com.
How to apply
Steps
1Clean and degrease the surface, then scuff as needed.
2Mask off surrounding panels and trim.
3Mix to the product's ratio and strain.
4Apply 2–3 even coats, flashing between each.
5Let cure fully before sanding, buffing, or assembly.
Specifications
Full data
Frequently asked
Good to know
This listing ships US Chemical & Plastics USC in a 1 (QT) container. Check the autofxmart catalog for other sizes and bulk pricing.
US Chemical & Plastics USC uses a mix ratio of 4:1. Always measure activators and reducers accurately to maintain film properties and pot life — deviating from the ratio can cause adhesion or curing problems.
Most in-stock orders for US Chemical & Plastics USC ship the same or next business day from our US warehouse. Expedited options are available at checkout. Freight-class items may require an additional 1–2 days for carrier pickup.
Yes. autofxmart is an authorized distributor of US Chemical & Plastics products. Every unit is factory-fresh, sealed, and backed by the manufacturer's standard warranty. If you have a concern, contact support@autofxmart.com and we will make it right.
The MPN for US Chemical & Plastics USC is 42-4. Use this number when cross-referencing against TDS, SDS, or legacy supplier catalogs.
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