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Dow Corning

Dow Corning DOWSIL 99180621 Silicone Sealant 10 oz Cartridge White

SKU CH-DENY-MYEQQ

Multipurpose white silicone sealant in a 10 oz cartridge resists temperatures from -49 to 392 °F, cures in one day and meets UL 94 V1

  • Multipurpose adhesion on concrete, glass, metal, wood and more
  • Flexible silicone joint survives vibration and structural movement
  • High-temperature resistance up to 392 °F for engine and exhaust areas
  • Low 29 g/L VOC content meets strict air-quality requirements
  • UL 94 V-1 flame rating adds fire-safety compliance

Multipurpose Silicone Sealant

DOWSIL 99180621 is a white silicone sealant supplied in a 10 oz cartridge for multipurpose bonding and sealing. It adheres to concrete, fiberglass, glass, masonry, metal, plastic and wood. The formula meets UL 94 V1 flammability standards and contains 29 g/L VOC content. It cures by moisture exposure to form a flexible, durable joint.

Builders needing high-temperature flexibility

This sealant suits projects that must withstand temperatures from -49 Degrees F to 392 Degrees F while remaining flexible after a full cure time of 1 day. It is not for buyers who require a non-silicone chemistry, a faster full cure than 1 day, or a container format other than a standard cartridge. The product is also restricted from sale in certain states.

Standard cartridge application

Installation uses a common caulking gun to dispense the 10 oz cartridge, providing a working time of 45 minutes for tooling and adjustment. Surfaces must be clean and dry for proper moisture-cure adhesion. Common issues include applying to contaminated substrates, which prevents bonding, or moving the joint before the 1 day full cure completes.

Highlights

  • Multipurpose adhesion on concrete, glass, metal, wood and more
  • Flexible silicone joint survives vibration and structural movement
  • High-temperature resistance up to 392 °F for engine and exhaust areas
  • Low 29 g/L VOC content meets strict air-quality requirements
  • UL 94 V-1 flame rating adds fire-safety compliance

Specifications

BrandDOWSIL

Questions about this item

What cartridge gun do I need for the 10 oz DOWSIL 99180621 cartridge?

A standard 10 oz caulking gun fits the cartridge and will dispense the sealant smoothly.

Can I apply this sealant over existing cured silicone on my bathroom fixtures?

Fresh DOWSIL 99180621 will bond to clean, fully cured silicone after the old surface is wiped with isopropyl alcohol and allowed to dry.

How do I confirm the bead has reached full strength after installation?

After one day the sealant forms a flexible rubber that withstands temperatures from -49 °F to 392 °F and meets the UL 94 V1 flammability rating.

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