<prompt> Entonox is combination of25 oxygen 25N2O50 oxygen 50N2O75 oxygen 25 N2O100 oxygen 0N2O  <response>: B. i.e. 50 oxygen : 50 N2O 132 - Lee s synopsis of anaesthesia 13th ENTONOX - is the trade name for a 50 - 50 mixture of gaseous N2O and O2 The cylinder shoulder is painted white and blue in quarters and body is blueUses include - obstetric analgesia, and analgesia for dressed wounds, coronary infarction and dental surgeryPIN number for oxygen - 2, 5 for Entonox- 7. Nitrous oxide 3, 5, air 1, 5 