304 Stainless Steel Durable and designed for year-round use, offering reliable performance. This model features a windproof stainless steel hose clamp for enhanced winter stability.Superior Ventilation and Consistent Performance: High-flow perforations enhance ventilation, while fine mesh helps reduce windblown debris buildup and facilitates chimney cap maintenance.Weatherproof Umbrella Design: The 360 tapered rain cap allows for rapid drainage, preventing water accumulation and backflow, ensuring unobstructed flue flow even in inclement weather.Strong and Reliable, Weatherproof (Optional Upgrade): An extended base and dual-side screw holes ensure a secure fit.Precisely Fits 8-inch Ducts: Designed for 8-inch outer diameter single-wall chimney pipes and PVC ducts.