Respiration monitors are tools that allow you to check your respiratory function at home. These include pulse oximeters, incentive spirometers, and peak flow meters. A pulse oximeter is a tool that quickly and easily reads the oxygen saturation in your body. Simply slip the oximeter onto your fingertip and wait for a reading. An incentive spirometer is a device that expands your lungs, allowing you to breath fully and more deeply. This product is often used by people recovering from surgery or who have a lung disease. A peak flow meter measures how well you are able to exhale air from your lungs. People with asthma use peak flow meters to monitor their symptoms, which can help prevent an asthma attack.