1Zinc Alloy and Carbon Steel: The joint is made of zinc alloy and carbon steel, which is wear resistant, durable, not easy to rust, and has a long service life. 2Function: The function of oxygen inhaler is to provide oxygen with constant pressure and flow for patients that is very practical. 3High Sensitivity Flowmeter: The flowmeter has clear scale, high sensitivity and accurate measurement, which is also easy to read. 4Detachable Humidifying Bottle: The humidifying bottle is detachable that is easy to clean and sanitary. After the gas is humidified through the humidification cup, the human body will be more moist and comfortable to inhale. 5Wide Applications: This oxygen gauge flow meter is suitable for use in hospitals, rash centers, home care and emergency situations.