The FB114 18 25 Grey Double Ply Black Poly from Mueller Streamline is an R-4.2 rated insulation sleeve designed for effective thermal performance. This product features a double ply construction, ensuring durability and resistance to wear. The grey exterior allows for easy identification during installation, while its dimensions provide a snug fit over pipes. Ideal for HVAC systems, this sleeve helps minimize energy loss, making it essential for energy-efficient installations. It meets all relevant industry standards for safety and performance.