Carlisle DS-321-WHITE-4-1 Duct-seal 321 Water Based Duct Sealant White 4-pack 1-gallon Pails

Product Description

The Carlisle DS-321-WHITE-4-1 Duct-Seal 321 is an industrial-grade, water-based duct sealant designed for use across a wide range of HVAC duct systems and materials. This case includes four 1-gallon pails of white sealant, giving HVAC technicians and contractors a ready supply for large-scale installation or service projects. The formulation is built on a synthetic latex base, making it solvent-free and non-toxic. It is safe for residential and commercial applications and meets strict environmental standards including SCAQMD Rule 1168, LEED compliance, and USDA, EPA, and FDA approvals.

Duct-Seal 321 bonds effectively to metal ductwork, glass fiber duct board, flexible duct, duct fabric, and flexible tubing runouts. This makes it one of the most versatile duct sealing compounds available for HVAC contractors. The sealant includes built-in fiber reinforcement for added tensile strength and resistance to cracking after cure. UV inhibitors are also incorporated into the formula, extending performance when the sealant is exposed to outdoor conditions. The product is UL 181 B-M Listed and passes both ASTM D-2202 and ASTM C-731 testing standards, confirming it meets the highest performance benchmarks for duct sealing in the HVAC industry.

Application is straightforward. The sealant can be applied at temperatures ranging from 35 degrees Fahrenheit to 110 degrees Fahrenheit. Once applied, it delivers coverage of up to 320 linear feet at 3 inches width and 20-mil thickness per gallon. Dry time is approximately 48 hours but may vary depending on ambient temperature and humidity. After curing, the sealant performs across a service temperature range of -20 degrees Fahrenheit to 200 degrees Fahrenheit, making it reliable in both cold-climate and high-heat HVAC environments. Shelf life is 12 months when stored properly. This product is manufactured in the USA.

• UL 181 B-M Listed and passes ASTM D-2202 and ASTM C-731 standards for duct sealing performance
• Built-in fiber reinforcement and UV inhibitors provide long-term durability indoors and outdoors
• Solvent-free, non-toxic, water-based formula meets LEED, SCAQMD Rule 1168, USDA, EPA, and FDA requirements

Product Highlights

The Carlisle DS-321-WHITE-4-1 Duct-Seal 321 delivers certified, fiber-reinforced duct sealing performance across metal, flex, and fiber board duct systems. Its water-based, solvent-free formula meets multiple regulatory approvals and is suitable for residential, commercial, and outdoor HVAC applications.

Product Information

Standard Information

• Brand: CARLISLE
• Manufacturer Part Number: DS-321-WHITE-4-1

Technical Specifications

• Color: White
• Composition: Synthetic Latex
• Application Temperature: 35 degrees Fahrenheit to 110 degrees Fahrenheit
• Service Temperature: -20 degrees Fahrenheit to 200 degrees Fahrenheit
• Coverage: Up to 320 linear feet at 3 inches width, 20-mil thickness
• Dry Time: 48 hours (may vary by temperature and humidity)
• Shelf Life: 12 months
• Flame Resistant: Yes
• Certifications: UL 181 B-M Listed, ASTM D-2202, ASTM C-731, LEED Compliant, SCAQMD Rule 1168, USDA Approved, EPA Approved, FDA Approved
• Country of Origin: USA
• Package Contents: 4 x 1-gallon pails
• Height: 7.5 inches
• Length: 7.75 inches
• Width: 7.75 inches
• Weight: 10.75 pounds
• Prop 65: Yes