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Gray 3M 525 polyurethane sealant cartridge 10 oz

3M

3M 525 Polyurethane Sealant 10 oz Cartridge Gray

SKU CH-4H65-W8VKR

Polyurethane sealant in a 10 oz cartridge stays flexible, resists cracks and mould, and meets ASTM C661 and D412 standards

  • Paintable finish suits interior and exterior projects
  • Flexible polyurethane handles joint movement up to 800 % elongation
  • Crack, mildew and mould resistant for durable weatherproofing
  • Works from -22 °F to 176 °F across seasonal extremes
  • 150-minute working time allows precise tooling before cure

Multipurpose Polyurethane Sealant

3M 525 is a polyurethane-based sealant supplied in a 10 oz cartridge for multipurpose bonding and sealing tasks. The gray compound cures to a flexible, nonshrinking bead that remains waterproof across a wide temperature range. It is suited for professional and DIY users who need a paintable joint sealant with proven crack, mildew and mould resistance.

800 Percent Elongation at Break

The single figure that determines suitability is the 800 percent elongation measured to ASTM D412. This high stretch capacity lets the cured sealant absorb joint movement without tearing or losing adhesion. If the application demands less movement accommodation, a lower-elongation product may be adequate, but dynamic joints require this level of flexibility.

Cartridge Application with 150 Minute Working Time

The sealant is dispensed from a standard cartridge using a caulking gun, so no specialised dispensing equipment is needed. A 150 minute working time allows extended tooling and adjustment before skin formation begins. Full cure is reached in one day, after which the joint withstands temperatures from -22 °F to 176 °F and can be painted to match surrounding surfaces.

Highlights

  • Paintable finish suits interior and exterior projects
  • Flexible polyurethane handles joint movement up to 800 % elongation
  • Crack, mildew and mould resistant for durable weatherproofing
  • Works from -22 °F to 176 °F across seasonal extremes
  • 150-minute working time allows precise tooling before cure

Specifications

Brand3M

Questions about this item

What does 800 percent elongation mean once the sealant is cured?

The cured bead can stretch to eight times its original length before breaking, so joints that move with temperature or vibration stay sealed.

What does meeting ASTM C661 and ASTM D412 tell me about real-world performance?

Those standards verify the sealant's hardness, tensile strength and elongation, confirming it will hold up to structural movement and weather exposure.

What size caulking gun or nozzle does the 10 oz cartridge need?

It fits any standard 10 oz cartridge gun and uses a typical screw-on nozzle tip for bead control.

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