Windkat is available in a variety of popular sizes to fit most flue pipes, chimney pots and chimney stacks. Windkat for Chimney Pots comes in 6 popular sizes from 125-296mm and is installed by slotting into the top of the pot. Simply choose the Windkat size that is 1mm to 10mm smaller than the internal diameter of your pot, thereby ensuring a snug and secure fit. We include a tube of heat resistant silicone to seal the fit. We can manufacture Windkat to virtually any size by special order. See the size Guide here