The newly designed silicon disposable laryngeal airway is now an easily recognisable ' PRO- Breath' blue. Constructed using super soft silicone which gives an optimum seal,. offer maximum patient comfort as well as reliability and durability. The size of the Laryngeal Airways is marked both on the tubing and on the air pressure valve which ensures you chose the correct size, and makings are show along the tubing to allow for a correct and easy insertion Size 4.