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White caulking compound in a rectangular 32 oz box

Nu-Calgon

Nu-Calgon 4216-92 Caulk 2 lb Slug White Thumb-Tite

SKU CH-JG1W-BWYWV

White caulking compound for duct applications, supplied as a 2 lb slug that remains flexible, non-hardening and waterproof from -20 °F to 350 °F

  • White finish resists UV and mildew for lasting appearance
  • Flexible seal stretches 500 % to handle joint movement
  • Non-hardening formula stays workable without full cure time
  • Waterproof and vapour-proof barrier protects duct applications
  • Performs from -20 °F to 350 °F in extreme conditions

Product Identity

Nu-Calgon 4216-92 is a white caulking compound supplied as a 2 lb slug for duct sealing work. It is formulated for installers and maintenance crews who need a flexible, non-hardening sealant that stays workable across a wide temperature range. The product ships new in a 32 oz box and is ready for immediate application.

Critical Specification

The sealant delivers 500 percent elongation and remains flexible from -20 degrees F to 350 degrees F without hardening, sagging or shrinking. This combination of extreme stretch and thermal stability is the single property that determines whether the material will survive repeated expansion cycles in duct systems.

Thermals Noise Power

Because the compound is non-hardening and vapor proof, it maintains its seal through continuous heating and cooling without cracking or losing adhesion. It produces no noise, draws no power and requires no cure time, so the joint stays watertight and mildew resistant throughout normal HVAC operation.

Highlights

  • White finish resists UV and mildew for lasting appearance
  • Flexible seal stretches 500 % to handle joint movement
  • Non-hardening formula stays workable without full cure time
  • Waterproof and vapour-proof barrier protects duct applications
  • Performs from -20 °F to 350 °F in extreme conditions

Specifications

BrandNU-CALGON

Questions about this item

How does the 500 percent elongation hold up once the sealant is applied in a real duct joint?

The 500 percent elongation lets the cured bead stretch significantly before breaking, so normal duct movement and vibration will not tear the seal.

What does the nonhardening property mean for the way this compound behaves after application?

Because it stays nonhardening, the material remains pliable and will not become brittle or crack as temperatures cycle between -20 and 350 degrees F.

Will the 32 oz box fit a standard caulking gun or does it need a special applicator?

The product is packaged as a 2 lb slug in a box, not a cartridge, so it is designed for hand‑press or bulk‑feed tools rather than a standard gun.

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