The FB114 06 25 Grey Double Ply Black Poly R-4.2 from Mueller Streamline is engineered for optimal insulation performance. Featuring a double ply design, this product provides an R-4.2 thermal resistance rating, ideal for various HVAC applications. Measuring 6 inches in diameter, it ensures effective temperature management. The grey poly finish not only enhances its appearance but also protects against environmental wear, making it suitable for both indoor and outdoor use. This lightweight insulation is easy to install and meets industry standards for quality and performance, making it a reliable choice for energy efficiency.