Oxygen Flowmeter Components.  Oxygen flowmeter content An oxygen flowmeter is a medical device used to control the flow of oxygen from an oxygen cylinder or pipeline into a patient's airways. The content of an oxygen flowmeter typically includes: Flowmeter tube: This is the main part of the device that controls the flow of oxygen to the patient. It is a transparent tube with markings indicating the flow rate in liters per minute (LPM). Control knob: This is a dial on the top of the flowmeter tube that adjusts the flow rate of oxygen to the desired level. Oxygen inlet: This is the port where the oxygen supply source (cylinder or pipeline) is connected to the flowmeter. Pressure gauge: Some oxygen flowmeters have a pressure gauge that indicates the pressure of the oxygen supply source. Humidifier bottle: This is a container filled with sterile water that attaches to the flowmeter and humidifies the oxygen before it is delivered to the patient. Oxygen tubing: This is a flexible tube that connects the flowmeter to the patient's airways. Overall, the content of an oxygen flowmeter is designed to ensure that the patient receives the correct amount of oxygen in a safe and effective manner.