1. What is it?

PU foam with a long stem is a specialized two-component polyurethane foam (1k pre-polymer and 2k systems also exist) dispensed from an aerosol can through an elongated, rigid plastic straw-like applicator. This stem allows for precise, deep, and targeted application into hard-to-reach cavities, gaps, and voids that are impossible to reach with a standard short nozzle.

2. What are the primary use cases?

Its primary use case is precision application in construction, manufacturing, and maintenance. Key applications include:

• Installing Doors & Windows: Snaking foam deep into the rough opening around a window or door frame to ensure complete insulation and sealing without overspray on visible surfaces.

• Deep Cavity Wall Insulation: Filling the deep voids in masonry, concrete blocks, or behind sheathing where a standard nozzle cannot reach, improving thermal and acoustic performance.

• Pipe & Conduit Sealing: Sealing around pipes, electrical conduits, and cables where they penetrate walls or floors, creating fire, smoke, and air seals deep within the penetration.

• HVAC & Ductwork Sealing: Applying foam into gaps around ducting in tight attic or crawl space areas.

• Automotive, Marine, and RV Manufacturing/Repair: Precise application for sound dampening, insulating irregular cavities in doors and body panels, and sealing compartments.

• Appliance Insulation: Filling specific cavities in refrigerators, freezers, or water heaters during manufacturing or repair.

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3. What problems does it solve?

• Incomplete Sealing: Standard nozzles can't reach deep enough, leaving gaps and cold bridges in the center of a wall cavity.

• Messy Overspray: The long stem delivers foam exactly where it's needed, minimizing waste and preventing unsightly foam on finished surfaces, bricks, or glass.

• Inefficient Use of Material: Allows users to fully empty the can by reaching into the deepest application points, ensuring no product is wasted.

• Difficulty Accessing Tight Spaces: Solves the problem of insulating and sealing cavities that are narrow, deep, or have complex geometries.

• Labor Inefficiency: Reduces the need for makeshift solutions like attaching tubes to short nozzles, which are often unstable and messy.

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