**304 Thick Stainless Steel Rotating Chimney Cowl Cap: Spinner Anti-Downdraught Fits Most Standard Chimney Pots Very effective in preventing wind and increasing ventilation.Protect your chimney from rain and moisture, which is especially suitable for chimneys that are not used frequently.Stainless steel construction Thickened fixed feet; **The base diameter is suitable for most standard chimneys, the base diameter is 100mm, 110mm, 150mm, 160mm, 200mm, 250mm,300mm, 350mm, 400mm, 450mm, 500mm, suitable for standard solid steel chimneys (fixed) **No Noise and Rainproof：Made of stainless steel, it is strong enough to withstand 200km/h wind speed and 100KG load without damage and deformation.stainless steel chimney cap is very effective windproof and increased ventilation. There is no noise when the roof ventilation fan rotates. If you have any questions, please do not hesitate to contact us. Thank you for coming, wish you a happy life！