Master Flow GreenBoot 8 in. x 4 in. to 4 in. Pre-Sealed and Pre-Insulated R-6 Register Box with Installations Rails

Master Flow Pre-Insulated Register Box with Installation Rails create a straight (in-line) transition from round pipe or insulated flexible duct to an air register or grill. They arrive ready-to-install, conveniently pre-wrapped in a foam insulation cap. The included Installation Rails attach to the flange or easy attachment to joists or other nailing surfaces. Design saves time during installation and energy without additional sealant or insulation.

• R6 insulation on outside of boot, not in air stream
• Durable galvanized steel construction
• Transition from round pipe or flex duct to a register grille