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Hardcast CCWI-181 White Duct Sealant 2 Gal UL181 HVAC Mastic

SKU: 304143

$87.99

Only 2 left in stock

Same-item volume pricing
QuantityUnit priceSaving
1–4$87.990%
5–9$83.595%
10+$79.1910%

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Hardcast CCWI-181 White Duct Sealant – 2 Gallon UL181 HVAC Mastic

The Hardcast CCWI-181 White Duct Sealant is a heavy-textured, water-based synthetic latex mastic designed for professional HVAC duct sealing applications. Reinforced with built-in polyester fibers, this premium sealant delivers exceptional strength and long-term durability.

Ideal for sealing duct joints, seams, flexible duct connections, and wall penetrations, CCWI-181 is UL listed and compliant with major industry standards.


🔧 Key Specifications:

  • 2 Gallon Pail

  • White Finish

  • UL 181 A-M & UL 181 B-M Listed

  • UL Listed 17NF

  • LEED Compliant

  • SCAQMD Rule 1168 Compliant

  • MFG# 304143


🔥 Ideal Applications:

  • HVAC Supply & Return Duct Sealing

  • Commercial & Residential Duct Systems

  • Sheet Metal & Flex Duct Joints

  • Indoor & Outdoor Installations

Product details

Part / SKU 304143

Package includes

  • Hardcast CCWI-181 White Duct Sealant 2 Gal UL181 HVAC Mastic

Included components and any stated pack quantity are as described in this listing. Optional accessories shown separately are sold separately unless expressly included above.

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