Vital Capacity (VC) refers to the total amount of gas that can be exhaled at one time when trying to inhale. Adult men's vital capacity is about 3500-4000 milliliters, and women's is about 2500-3000 milliliters. The better the health, the greater the vital capacity. Spirometer is a portable, handheld device to measure your ability to exhale air from your lungs and can provide accurate data to reflect tracheal ventilation. The importance of vital capacity: Lung vital capacity is closely related to human respiration. Physiological studies show that the organs, systems, tissues, and organs of the human body Spirometry (low values compared to normal values), indicating that the body's oxygen uptake and discharge, the oxygen supply inside the body is not sufficient, once the body needs a large oxygen consumption situation (such as long-term learning, work, strenuous exercise) will occur a serious lack of oxygen supply, resulting in adverse reactions such as headache, dizziness, chest tightness, listlessness, inattention, memory loss, insomnia, this will not only affect learning and work, but also cause many irreparable losses to health. Usage Method: 1. move the red movable buoy to the starting point. 2. use your mouth to hold the blue mouthpiece, take a deep breath, hold your breath, blow out a breath, and try to blow the buoy farther away. 3.observe the scale of the floating buoys. The average adult man can reach 400L/min, women can reach 350L/min, and athletes and vital capacity can reach 600-700L/min. (routinely calculated in milliliters ml. This lung activity meter is measured by rising L. The conversion is as follows: if the scale you measure is 400L/min, the conversion to common units is 4000ml/min. How to use the peak flow meter Turn the red pointer to the starting point of the ruler, and the fingers of the peak flow meter do not interfere with the pointer's activity. Stand up and take a deep breath. Peak flow meter's mouthpiece into the mouth, lips tightly wrapped with mouthpiece, forced a quick breath. Record the value of the red pointer and turn the pointer to the starting point Repeat the above action three times in a row and take the best value. What should be paid attention to is: with the greatest strength and fastest speed to exhale; lips tightly wrap the mouthpiece, cannot leak; do not block the hole with the tongue, mouthparts. If you want to repeat the test, please note that the red marker pointer should be turned to the lowest point of the scale before each test. The package includes: 1 pc Spirometer (Adult or child, Color random)