Gas cylinder with single pin index
Entonox has an pin index number of 7 . Air - 1 , 5 ; Oxygen- 2 , 5 ; N20 - 3 , 5 . CO2 - 1 ,6 ; Cyclopropane - 3 , 6 ; Heliox - 4 , 6 . PIN index number is developed to prevent incorect cylinder attachment .
Oxygen
Air
Titrogen
Entonox
Anaesthetic equipments