Spark insert made to insert in the neck of your chiminea. Screen insert may be required by city ordinance for use of your chiminea. Screen size will not affect airflow, allowing your fire to burn efficiently. Screen will stop drifting paper or other unwanted refuse from the fire. Always burn a seasoned hardwood such as Oak to reduce emissions and sparking. Burning large amounts of paper or using a chiminea as an incinerator is not recommended. Diameter of the insert is 6 1/4 inches.