Thick Stainless Steel Rotating Chimney Cowl Cap: Spinner Anti-Downdraught Fits Most Standard Chimney Pots Very effective in preventing wind and increasing ventilation. Hat designed to rotate with the action of the wind, so that the more the wind blows, the more the blades rotate, and the more powerful the air intake is from the inside out. Base diameter fits most standard Chimney with base diameter will fit standard Chimney pots, robust stainless steel construction (Note: This product is shipped in bulk, use requires assembly) Protect your Chimney from rain and moisture, which is especially suitable for chimneys that are not used frequently.Stainless steel construction Thickened fixed feet; include complete fixing kit Rotating hood for ventilation pipes, chimneys, and air extraction.The gairing provides maximum protection without hindering the performance of the chimney.