A-Maze-N 12" Expandable Smoking Tube. It generates smoke for 4 hours in the 12" position and extends to 18" for 6 hours of smoking. Ideal for cold smoking or enhancing smoke flavor in your grill or smoker at temperatures above 225 degrees Fahrenheit. It conveniently uses wood BBQ pellets. This durable smoking tube comes with a 1-year warranty for factory defects.