The Field Controls 01580101 Draft Control 9RC with collar 9" RC is a 9" RC for oil or coal-fired furnace or boiler heating equipment. It is made of durable metal for long-lasting use. The collar prevents drafts from entering the furnace or boiler, ensuring consistent heating. The Field Controls 01580101 Draft Control 9RC with collar 9" RC is a 9" RC for oil or coal-fired furnace or boiler heating equipment. It is made of durable metal for long-lasting use. The collar prevents drafts from entering the furnace or boiler, ensuring consistent heating.