The MR810 respiratory gas humidifier is designed to heat and humidify gases delivered to the patient during mechanical ventilation or other types of respiratory systems, when the gas mixture flow is maintained at a constant level. The possibility of heating the inspiratory line allows for effective humidification of the gas mixture and prevents the formation of condensate in the circuit. MR810 is a simple model, it has two modes of operation - with heating of the circuit using a heating wire placed inside the circuit and passive heating of the air flow passing through the chamber. The modes are selected automatically in the presence or absence of a heating wire. Temperature control is carried out using a miniature thermometer installed in the tee of the circuit in front of the patient.