 Generally, the distal tube (tube two, clear) enters the esophagus, where the cuff is inflated and ventilation is provided through the proximal tube (tube one, blue) which opens at the level of the larynx.In the rare instance where the distal tube intubates the trachea, ventilation is provided through the distal tube.Inflation of the cuff in the esophagus allows a level of protection against aspiration of gastric content similar to that found in the laryngeal mask.