Mo's Smoking Pouch is essential for gas grills. It is an envelope of mesh 304 stainless steel that holds wood chips or pellets. The airspaces in the mesh are small enough that they limit the amount of oxygen so the wood smolders. Put it on top of the cooking grate, on the burners, on the coals. It holds enough wood for about 15 minutes for short cooks, so you need to refill it or buy a second pouch for long cooks like pork shoulder and brisket. Meathead says his has survived more than 50 cooks and he likes it better than the smoker tubes.