1. breathing circuit is made up of parallel wye, tube, cuff and breathing bag. they are made of special material, the corrugated tubes have a good flexibility and bending resistance, not meander, not broken which make sure to supply air smoothly in mechanical ventilation; 2. breathing circuit uses standard cuff which can connect reliable with monitoring devices and use simple and convenient in clinical; 3. it has no irritation on human skin and mucosa, and no allergic reaction and other damage; 4. meets international standard iso5367:2000 and industry standard yy0461_2003; 5. it has obtained ce certificate and we undertake oem orders.