Target chimney/flue cleaning brushes are available in wire for cleaning ceramic flues and chimneys, and polypropylene (synthetic nylon) for cleaning metal flues and chimneys. Choose from a complete range of standard sizes and shapes with 1/4" NPT connectors. Heavy-duty brushes are offered with 3/8" NPT connectors. Contact customer service for oval-shaped chimney brushes or other sizes that are not listed.