An expanding foam gun is an essential tool for applying professional-grade polyurethane (PU) foam with maximum precision and efficiency. Unlike cans with a simple straw applicator, this heavy-duty metal tool (often with a Teflon coating) screws onto the can, offering adjustable flow control via a trigger and a rear valve.

This design allows the user to accurately fill gaps, joints, and narrow cavities around windows, doors, pipes, and insulation, significantly minimizing waste and messy application. It’s a crucial investment for achieving a durable, airtight, and professional seal in any construction or DIY project.