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

SKU: 304143

Weight	26 lbs
Dimensions	13 × 12 × 12 in

$87.99

In stock — available to order.

Sold individually. Each quantity ordered is one unit. Kits are one complete kit; products sold by length use the stated length unit.

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Quantity	Unit price	Saving
1–4	$87.99	0%
5–9	$83.59	5%
10+	$79.19	10%

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

Specifications & product details

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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