The convection fan blade works in conjunction with the convection fan motor by turning to circulate the hot air through the oven for even heating. The fan blade attaches to the convection motor shaft and is secured by the blade nut. If the part is damaged or worn you will need to replace it. This part is made from metal and measures approximately 5” in diameter. Please remember to disconnect the power to the oven before starting your repair. This is a genuine OEM part and is sold individually.