SEM 39684 Self-Etching Primer, Gray () is a professional acid-etch primer for bare metal preparation in automotive collision repair. The acid-etch chemistry chemically bonds to bare steel, aluminum, and galvanized metal substrates — providing molecular-level adhesion that mechanical bite alone cannot match. No separate metal conditioner or conversion coating step required: SEM Self-Etching Primer treats, conditions, and primes the metal surface in a single application.
Quart size for spray gun application on medium repairs and production use. Gray-colored formula provides visual contrast for coverage verification against bare metal. Compatible with waterborne and solvent-borne topcoat systems.
- Color: Gray
- Size:
- Type: Single-Component Self-Etching Primer
- Substrates: Bare steel, aluminum, galvanized metal
- Application Method: Spray gun
- Topcoat Compatible: Waterborne and solvent-borne systems
- Country of Origin: USA
- Part Number: 39684
SEM Self-Etching Primer is a core shop supply for any collision center performing bare metal repairs. Available in aerosol, quart, and gallon sizes — stock all three formats for maximum workflow flexibility.
