The whole machine adopts pneumatic gas control technology without any power supply, which strictly avoids the high risk brought by the mixing of power supply and high-pressure gas cross-installation. ● Standardly equipped with DVR respirator, with on-demand respiration and manual air supply function, can also provide positive pressure oxygen supply, for patient's postoperative resuscitation and emergency airway management. ● Laughing gas concentration is adjustable from 0-70%, and oxygen concentration is always guaranteed to be no less than 30%, which is safe and reliable. Adopting the patented precise titration technology and exhaust gas treatment technology, effectively removing the exhaust gas, preventing environmental pollution and harm to doctors. Gas safety alarm, once the oxygen is out of gas, the supply of laughing gas will be interrupted automatically and an alarm sound will be issued. ● Optional gas flow controller, visualizing the total gas flow (enhanced) ● Optional T-type safety valve (enhanced), can start the air supply when there is a failure of gas supply. ● Clinical verification by hundreds of famous hospitals, the effectiveness and safety are widely recognized.