I bought this to bring down the chimney on my meat smoker. It fit great! Tried the Home Depot aluminum duct, no bueno. This one allows your smoker to evacuate low, cold air and little smoke, using less chips and better temp control. No modifications needed or cutting, drilling, welding or anything! Just drop it in, still use the damper to control airflow, stretch if needed to reach the lower grates on your grill, keep an eye on your temp (I recommend 225F) and 8 hours after = Delicious Smoked Meat!