5 Lbs. Duct Seal Putty, Slug Box, Gray, Thumbable

MARS 93521 Duct Seal Putty – 5 lb Slug Box, Dark Gray

The MARS 93521 Duct Seal Putty is a professional-grade, non-hardening sealing compound formulated for mechanical, electrical, and HVAC applications. This malleable, reusable material provides an airtight and watertight barrier for sealing penetrations in walls, foundations, junction boxes, conduits, and refrigeration line entries. Engineered for long-term pliability, MARS duct seal maintains its consistency over time without cracking, drying, or shrinking, ensuring reliable sealing performance under varying environmental and temperature conditions.

Technical Specifications

• Manufacturer: MARS
• Product Name: Duct Seal Putty
• Part Number: 93521
• Packaging Type: Slug Box
• Package Weight: 5 lb (2.27 kg)
• Form: Solid, Hand-Moldable Compound
• Color: Dark Gray
• Texture: Thumbable / Non-Hardening
• Specific Gravity: 1.78 g/cc
• Flash Point: 310°F (COC)
• Flammability Rating (HMIS): 0
• Toxicity: Non-Toxic
• Adhesion Properties: Excellent adhesion to metal, masonry, plastic, and wood substrates
• Temperature Resistance: Maintains flexibility and seal integrity under normal mechanical and environmental operating ranges
• Reusability: Can be reshaped and reapplied as needed
• Weather Resistance: Resistant to air and moisture infiltration
• Applications: Sealing around electrical boxes, conduit entries, refrigeration tubing penetrations, foundation wall openings, and HVAC ductwork connections
• Compliance: Meets industry requirements for non-hardening mechanical sealing compounds

Performance and Application

The MARS 93521 Duct Seal Putty is designed for versatile use across multiple trades including electrical, HVAC, plumbing, and refrigeration. Its non-hardening formulation allows it to conform tightly to irregular shapes and surfaces, maintaining an effective seal against air, dust, and moisture intrusion. The putty can be hand-applied without tools and removed or repositioned as needed during system maintenance or equipment servicing. With no volatile components, it remains stable over extended periods, even when exposed to moderate heat or temperature cycling. The 5 lb slug box packaging provides a convenient quantity for field use on large projects or repetitive installations.

Summary

The MARS 93521 Duct Seal Putty offers a durable, non-hardening, and reusable sealing compound for professional HVAC, electrical, and mechanical installations. With excellent adhesion, temperature stability, and environmental resistance, it provides dependable long-term sealing performance for junction boxes, conduits, and system penetrations in both residential and commercial applications.