3M MSP Seam Sealer

SKU #3M-08370
• Fast curing and immediately paintable
• For interior and exterior body joints
• Excellent adhesion to primed metal and aluminum
  • Description
  • Reviews
  • Tech Sheets

high quality, heavy-bodied, general purpose, moisture-curing seam sealer for interior and exterior body joints.

  • Excellent adhesion to primed metal and aluminum
  • Fast curing and immediately paintable
  • Very low solvent percentage
  • Excellent shelf life
  • No problems with alcohol-containing solvents


  • Minimal opportunity for bond failure
  • No need to wait to move the car into the paint area
  • Minimal airborne solvent during curing process
  • Product stays usable for longer than standard seam sealers
  • Product will cure even if contacted with alcohol-containing solvents


  • Fewer comebacks for seam sealer failure
  • Save and make money by eliminating time waiting to paint seam sealer
  • Minimal solvent odor or health issues
  • Less product waste because past its shelf life
  • No rework because solvents inhibited seam sealer cure


  • Container: 310 ml Flexpak
  • Base: Modified Silane Polymer
  • Density lbs/Gallon (Appx.): 11.9
  • Color: White
  • Flash Point: 144°F
  • Viscosity (CPS) Brookfield Viscometer: 1,000,000 CPS
  • Solids Content (Appx.): 97%
  • Consistency: Heavy Paste

Product Uses

  • General purpose automotive seams, including door skins, rocker panels, rear body panels, trunk seams, floor pans, etc.

Performance Properties

  • Cold Temperature Resistance @ -20°F: (Remains Flexible)
  • Heat Resistance - 8 Weeks @ 200°F: (No Degradation)
  • Adhesion
    • Primed Metal: Excellent (Cohesive Failure)
    • Bare Metal: Excellent (Cohesive Failure)
  • Tensile- Appx. 120 PSI
  • Elongation- Appx. 350%

Directions for Use

  1. Always apply over automotive primer. Applying over bare metal will not provide enough corrosion protection. Acid etching primer is not recommended; if used, be sure to allow to fully cure before applying seam sealer, or residual acid can weaken the bond.
  2. If necessary after priming, clean and dry surface with 3M General Purpose Adhesive Cleaner, PN 08984. Do not use an adhesive cleaner until the primer has fully cured.
  3. Install foil package into barrel of 3M Flexible Package Applicator Gun, P.N. 08398.
  4. Using a scissors, cut a small opening across the top end of package and fold back flaps.
  5. Place nozzle over the opened end onto the gun barrel.
  6. Replace the retaining collar.
  7. Cut nozzle to provide desired bead size.
  8. Apply seam sealer and tool (if necessary) to desired finished appearance. Alcohol solvents will not stop the curing process.
  9. The product is immediately paintable. If tooled with solvent, allow solvent to fully evaporate before painting.
  10. After use, dispose of both nozzle and empty package.

This item can only ship by ground within the Continental US.
Next Day or 2nd Day, AK & HI, & International delivery not available.

PROP65 Warning WARNING: This product contains a chemical known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warning.ca.gov.

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