<prompt> All true about microlaryngoscopy tube MLT except:-These tubes comes in these sizes 4.0, 5.0 and 6.0 mmIt is paicularly useful for laryngeal surgeryIt is longer than standard ETTThere is relatively low resistance to gas flow in there tubes.  <response>: These tubes come in three sizes, 4.0, 5.0 and 6.0mm. The size 5.0mm tube is the most commonly used. Microlaryngoscopy tube MLT vs. standard ETT The MLT is often used in place of a standard small diameter ETT to facilitate Direct Laryngoscopic procedures utilizing Microlaryngoscopy techniques. The surgeon prefers a small diameter ETT to facilitate the view of the airway. 