This set is the simplest and least expensive tool we know of to measure vital capacity, which is the volume of air a person can expel after taking the deepest possible breath. This set can also be used to compare effects of height, age, physical activity, and smoking. It includes four heavy-gauge plastic bags calibrated to six liters, four holders, and four mouthpieces.
How is savings calculated? We
multiply the savings per unit (in parenthesis) times the
total units of the original product.